The Emperor Dragonfly Chinese hacker group, notorious for frequently switching between several ransomware families to avoid detection, has been connected to the Cheerscrypt virus.
The attacks were linked by the cybersecurity company Sygnia to a threat actor also dubbed Bronze Starlight and DEV-0401. The hacking gang seems to be a ransomware operation, but past research suggests that the Chinese government is interested in many of its victims.
Cheerscrypt is the most recent addition to a long range of ransomware families that the gang has previously used, including LockFile, Atom Silo, Rook, Night Sky, Pandora, and LockBit 2.0 in a little over a year.
Recently, Sygnia researched a Cheerscrypt ransomware operation that utilized Night Sky ransomware TTPs. The attackers then dropped a Cobalt Strike beacon linked to a C2 address formerly tied to Night Sky operations.
The code for the Babuk ransomware, which was exposed online in June 2021, was used to develop the Cheerscrypt ransomware family, which Trend Micro first analyzed in May 2022. Cheerscrypt is one of several ransomware families used by the APT organization. The DEV-0401 group, unlike other ransomware gangs, oversees every stage of the assault chain directly, from the first access to the data theft. It does not rely on a system of affiliates.
A significant Log4Shell vulnerability in Apache Log4j was utilized by hackers in January 2022 assaults to acquire initial access to VMware Horizon servers. They subsequently dropped a PowerShell payload that was used to send an encrypted Cobalt Strike beacon. Apart from the beacon, the hackers also sent three Go-based tools: a keylogger that sent keystrokes to Alibaba Cloud, a customized version of the internet proxy tool iox, and the tunneling program NPS.
Trend Micro initially identified Cheerscrypt in May 2022, highlighting its capacity to target VMware ESXi servers as a component of a tried-and-true strategy known as double extortion to force its victims into paying the ransom or risk having their data exposed.
The hackers break into networks, take information, and encrypt devices just like other ransomware groups that target businesses. The victim is then coerced into paying a ransom through double-extortion methods using the data. The stolen data is posted on a data leak website when a ransom is not paid.
A PowerShell payload that can deliver an encrypted Cobalt Strike beacon has been dropped on VMware Horizon servers by infection chains that have exploited the major Log4Shell vulnerability in the Apache Log4j library.
Cheerscrypt and Emperor Dragonfly share initial access vectors, and lateral movement strategies, including the use of DLL side-loading to distribute the encrypted Cobalt Strike beacon. Notably, the ransomware gang is acting as a 'lone wolf' separated from the rest of the cybercrime community rather than as a RaaS (Ransomware-as-a-Service) platform for affiliates.
