Maverick fast-attack ransomware group FIN12 is quickly expanding

Today, security company Mandiant issued a report tracking the growth of a ransomware attack group it calls FIN12.

The company said the group is one of the most aggressive ransomware attackers ever seen, making up a fifth of all the cases it has handled since September 2020. FIN12 is also shifting its techniques and targets as it evolves.

FIN12 hits big targets with average annual revenues of $6 billion, said Mandiant. Although it has focused largely on North American victims since emerging in 2018, it has expanded to hit organizations in Australia, Colombia, France, Indonesia, Ireland, the Philippines, South Korea, Spain, the United Arab Emirates, and the United Kingdom.

The attackers differ from other groups in important ways. Unlike many of its peers, FIN12 relies on a large number of quick attacks and rarely bothers with double-dipping attacks that threaten to publish victims’ stolen data. This saves it time dwelling in a victim's network to exfiltrate data.

FIN12’s attacks take less than two days on average, compared to an industry median of five days. It also relies on third-party criminal groups to gain initial access to victims' systems and create a steady pipeline of targets.

FIN12 has a history of targeting hospitals, even during the pandemic when many other groups avoided hitting health care providers. Around one in five of its victims are in the healthcare industry, Mandiant said.

The attack group began by partnering with threat actors that used the TrickBot banking trojan and Empire PowerShell-based malware for post-breach exploitation, but recently sought new tools to expand its capabilities.

It began using the Bazarloader malware in September 2020, and Cobalt Strike Beacon is also a key part of its arsenal. Once it has established a footprint in its targets' networks, it almost always deploys the Ryuk ransomware tool to encrypt its victims' data.

Mandiant believes FIN12 is a Russian-speaking group likely residing in the Commonwealth of Independent States (CIS). It has not targeted organizations in that region, the report noted.