A threat actor appears to have repurposed the REvil ransomware to create their own ransomware family and possibly launch a ransomware-as-a-service (RaaS) offering.
Also known as Sodinokibi, REvil has become one of the most prominent ransomware families out there, being involved in a large number of high-profile attacks, including the one on JBS, the world’s largest meat processing company.
REvil is offered by an Eastern Europe/Russia-based threat actor tracked as PINCHY SPIDER, which is known for their RaaS business that previously involved the GandCrab ransomware, which was retired in June 2019, two months after REvil emerged.
On Tuesday, security researchers with Secureworks, which tracks REvil’s operators as GOLD SOUTHFIELD, revealed that a new ransomware family that is making the rounds appears to be nothing more than a repurposed REvil iteration created by a threat actor referred to as GOLD NORTHFIELD.
“[Secureworks Counter Threat Unit] analysis confirmed that the GOLD NORTHFIELD threat group, which operates LV, replaced the configuration of a REvil v2.03 beta version to repurpose the REvil binary for the LV ransomware,” the researchers say.
Furthermore, they note that the LV ransomware hasn’t been advertised on underground forums yet, but changes in partner and campaign IDs, as well as “the practice of naming and shaming victims” suggests that the threat actor is readying their own RaaS offering that involves LV.
Analysis of the LV ransomware has revealed identical code structure and functionality compared to REvil, while the observed changes would suggest the use of a hex editor to remove certain characteristics from the binary. The adversary also replaced the REvil configuration with their own. The threat actor also had to bypass REvil’s anti-tamper controls.
“If done correctly, the binary will successfully execute using LV’s updated configuration. Files on the victim’s system will be encrypted with session keys that are protected by LV’s public key, and victims will be directed to LV’s ransom payment site via the updated ransom note,” Secureworks says.
When visiting the payment site, the victim is asked for the key from the ransom note. To date, the researchers identified three Tor domains specified in LV ransom notes, but attempts to enter the required keys resulted in HTTP errors.
The researchers also discovered two leak sites associated with the LV ransomware and discovered that the threat actor names and shames victims, likely in an attempt to coerce them into paying the ransom. The adversary also posts screenshots of stolen files on the leak sites, and threatens to make the stolen information public unless the victim makes contact within 72 hours.
However, according to Secureworks, the threat actor hasn’t published any sensitive information stolen from its victims yet.
Related: Double Extortion: Ransomware’s New Normal Combining Encryption with Data Theft
Related: Sodinokibi Ransomware Operators Target POS Software
