The financially-motivated hacker group FIN11 has switched tactics starting using ransomware as the main monetization method.
The group carried out multiple high-volume operations targeting companies across the world, most of them in North America and Europe.
In recent attacks, the group was observed deploying the Clop ransomware into the networks of its victims.
Since August, FIN11 started targeting organizations in many industries, including defense, energy, finance, healthcare, legal, pharmaceutical, telecommunications, technology, and transportation.
Researchers from FireEye’s Mandiant observed FIN11 hackers using spear-phishing messages distributing a malware downloader dubbed FRIENDSPEAK.
“Recently, FIN11 has deployed CLOP ransomware and threatened to publish exfiltrated data to pressure victims into paying ransom demands.” reads the analysis published by FireEye. “The group’s shifting monetization methods—from point-of-sale (POS) malware in 2018, to ransomware in 2019, and hybrid extortion in 2020—is part of a larger trend in which criminal actors have increasingly focused on post-compromise ransomware deployment and data theft extortion.”
The attack chain starts when the victims enable the macro embedded in an Excel spreadsheet that came with the phishing e-mails.
The macros download and execute the FRIENDSPEAK code, which in turn downloads the MIXLABEL malware.
Experts also reported that the threat actor modified the macros in Office documents used as bait and also added geofencing techniques.
TA505 also deployed the Clop ransomware in its malware campaigns and recently started exploiting the ZeroLogon critical flaw to compromise targeted organizations.
“Attribution of both historic TA505 activity and more recent FIN11 activity is complicated by the actors’ use of criminal service providers. Like most financially motivated actors, FIN11 doesn’t operate in a vacuum. We believe that the group has used services that provide anonymous domain registration, bulletproof hosting, code signing certificates, and private or semi-private malware.” reads the analysis. “Outsourcing work to these criminal service providers likely enables FIN11 to increase the scale and sophistication of their operations.”
The experts pointed out that the FIN11 actors after dropped the Clop ransomware did not abandon the target after losing access, at least in one case they re-compromised the target organization a few months later.
The researchers believe FIN11 operates from the Commonwealth of Independent States (CIS – former Soviet Union countries).
The experts observed Russian-language file metadata in the code of the malware and reported that the Clop ransomware was only deployed on machines with a keyboard layout used outside CIS countries.
Mandiant researchers speculate FIN11 will continue to target organizations with sensitive proprietary data and that will likely pay the ransom to recover their operations after the attacks.
(SecurityAffairs – hacking, FIN11)