FBI Warns Organizations of Diavol Ransomware Attacks

The Federal Bureau of Investigation (FBI) this week shared a series of indicators of compromise (IoCs) associated with the Diavol ransomware family.

Diavol was initially detailed in July 2021 as a new tool in the arsenal of Wizard Spider, the cybercrime group known for operating the TrickBot botnet and the Conti and Ryuk ransomware families.

As part of a typical Diavol attack, in addition to deploying the ransomware to encrypt files on compromised systems, the threat actor claims to exfiltrate the victim’s data and uses that as leverage, threatening to publish the data online if the victim doesn’t pay the ransom.

While Wizard Spider has set up a Tor site on which it names victims and publishes files stolen during Conti ransomware attacks, no data stolen from the organizations targeted with Diavol has been leaked online yet, the FBI says.

The Bureau also notes that Diavol ransom payment demands have ranged from $10,000 to $500,000 so far and that the attackers showed willingness to engage in negotiations with their victims, ultimately accepting lower payments.

Diavol, which employs RSA encryption, was observed focusing on specific file types, based on a list defined by its operators. The malware appends the “.lock64” extension to the encrypted files and drops a ransom note instructing victims to access a Tor website to receive a decryption key.

The ransomware was observed generating for each victim computer a unique identifier (which is nearly identical to that employed by TrickBot) and then attempting to connect to a hardcoded command and control (C&C) server.

The FBI encourages Diavol victims to share any information they can on the attacks and points out they should not pay a ransom, as that would not guarantee the recovery of the encrypted/stolen data.

Organizations can mitigate the risk of ransomware attacks through data backups (including offline, password-protected backups), network segmentation, multi-factor authentication, employee training, and by using anti-malware solutions on all systems.

Related: Many Ransomware Attacks on OT Organizations Involved Ryuk: IBM

Related: VirusTotal Introduces ‘Collections’ to Simplify IoC Sharing

Related: FBI: 16 Conti Ransomware Attacks Targeted Healthcare, First Responders in U.S.