We have encountered a security threat in one of our RHEL servers which says the SSH server is configured to use Cipher Block Chaining. As far as I know, the RHEL systems provide security updates through their RHN satellite which can be achieved just by running the yum update command. But, how can I know if the security patch is applied to my RHEL system? P.S: I know the CVE number of the vulnerability/threat/issue. So my question is, is it possible for me to verify that the RHEL yum update command has fixed the bug in my system?
check if latest openssh patch provided by RHEL is installed
rpm;openssh
You can check this with yum-plugin-security:--cve  This option includes packages that say they fix a CVE - Common       Vulnerabilities and Exposures ID (http://cve.mitre.org/about/),       Eg. CVE-2201-0123.So try:yum --cve <Your CVE here> info updatesAnd you can check the changelog coressponding to the packages to check information about bug fixed:$ rpm -q --changelog openssh | grep -i cve- change default value of MaxStartups - CVE-2010-5107 - #908707- merged cve-2007_3102 to audit patch- fixed audit log injection problem (CVE-2007-3102)- CVE-2006-5794 - properly detect failed key verify in monitor (#214641)- CVE-2006-4924 - prevent DoS on deattack detector (#207957)- CVE-2006-5051 - don't call cleanups from signal handler (#208459)- use fork+exec instead of system in scp - CVE-2006-0225 (#168167)