Security researchers discovered a new ransomware family called Unnam3d that moves targeted files into protected RAR archives and demands an Amazon gift card as ransom.
Bleeping Computer first learned about the malware after a user submitted a sample to its site and asked for help in recovering stolen files. Currently distributed via email, the cyberthreat first extracts a bundled WinRar.exe executable to the %Temp% folder. It then executes a command to move the victim’s files stored in Documents, Pictures and Desktop to a specific directory in a password-protected archive. At that point, the ransomware displays a ransom note demanding that the victim send a $50 Amazon gift card in exchange for the archive’s password.
The developer of Unnam3d told Bleeping Computer they conducted an attack campaign near the end of March in which they sent out around 30,000 emails. These messages were disguised as correspondence from Adobe warning the recipient to update their Flash Player software. Clicking on the “update” link subsequently downloaded the ransomware.
Ransomware’s History With Gift Cards and Adobe Flash
Unnam3d isn’t the only cyberthreat that’s demanded gift cards as ransom payments. In March 2017, for instance, researchers at Lookout spotted a scareware campaign in which scammers blocked victims’ use of Mobile Safari until they received an iTunes gift card. In December 2017, Quick Heal Security Labs spotted an Android ransomware family demanding that victims submit an iTunes gift card as their ransom payment.
This also isn’t the first time a threat has masqueraded as an Adobe Flash Player update. For example, Heimdal Security observed attackers using the disguise to distribute Bad Rabbit ransomware back in October 2017. A year later, Palo Alto Networks discovered some threat actors leveraging fake Flash Player updates to push cryptocurrency miners onto unsuspecting users.
How to Defend Against Threats Like Unnam3d
Security professionals can help defend their organizations against threats like Unnam3d by using an endpoint management solution that allows them to inventory all endpoint devices and manage their configurations. Organizations should complement this visibility with a tool that uses artificial intelligence to determine the legitimacy of certain behaviors and mitigate the impact of zero-day malware.
David Bisson is an infosec news junkie and security journalist. He works as Contributing Editor for Graham Cluley Security News and Associate Editor for Trip...