surveillance of the victim's systems to find potential data targets and weaknesses. Mobile ransomware With the increased popularity of ransomware on PC platforms, ransomware targeting mobile operating systems has also proliferated. Typically, mobile ransomware payloads are blockers, as there is little incentive to encrypt data since it can be easily restored via online synchronization. Mobile ransomware typically targets the Android platform, as it allows applications to be installed from third-party sources. The payload is typically distributed as an APK file installed by an unsuspecting user; it may attempt to display a blocking message over top of all other applications, while another used a form of clickjacking to cause the user to give it "device administrator" privileges to achieve deeper access to the system. Different tactics have been used on iOS devices, such as exploiting iCloud accounts and using the Find My iPhone system to lock access to the device. On iOS 10.3, Apple patched a bug in the handling of JavaScript pop-up windows in Safari that had been exploited by ransomware websites. It recently has been shown that ransomware may also target ARM architectures like those that can be found in various Internet-of-Things (IoT) devices, such as Industrial IoT edge devices. In August 2019 researchers demonstrated it's possible to infect DSLR cameras with ransomware. Digital cameras often use Picture Transfer Protocol (PTP - standard protocol used to transfer files.) Researchers found that it was possible to exploit vulnerabilities in the protocol to infect target camera(s) with ransomware (or execute any arbitrary code). This attack was presented at the Defcon security conference in Las Vegas as a proof of concept attack (not as actual armed malware). Notable attack targets Notable software packages Reveton In 2012, a major ransomware Trojan known as Reveton began to spread. Based on the Citadel Trojan (which, itself, is based on the Zeus Trojan), its payload displays a warning purportedly from a law enforcement agency claiming that the computer has been used for illegal activities, such as downloading unlicensed software or child pornography. Due to this behaviour, it is commonly referred to as the "Police Trojan". The warning informs the user that to unlock their system, they would have to pay a fine using a voucher from an anonymous prepaid cash service such as Ukash or paysafecard. To increase the illusion that the computer is being tracked by law enforcement, the screen also displays the computer's IP