AnteFrigus ransomware actively spreading in the wild

November 15, 2019

The SonicWall Capture Labs Threat Research Team observed reports of a new variant family of ANTEFRIGUS ransomware [ANTEFRIGUS.RSM] actively spreading in the wild.

The ANTEFRIGUS ransomware encrypts the victim’s files with a strong encryption algorithm until the victim pays a fee to get them back.

Infection Cycle:

The ransomware adds the following files to the system:

  • Malware.exe
    • % App.path%\ <Random>-readme.TXT
      • Instruction for recovery
    • %App.path%\ [Name]. <Random>

Once the computer is compromised, the ransomware runs the following commands:

The ransomware encrypts all the files and appends the [<Random>]  extension onto each encrypted file’s filename.

After encrypting all personal documents, the ransomware shows the following text file containing a message reporting that the computer has been encrypted and to contact its developer for unlock instructions.

 

The ransom note contains instructions to an .Onion website in order to decrypt files.

It is a webpage that is located on the TOR network:

We have been monitoring varying hits over the past few days for the signature that blocks this threat:

SonicWall Capture Labs provides protection against this threat via the following signature:

  • GAV: ANTEFRIGUS.RSM (Trojan)

This threat is also detected by SonicWALL Capture ATP w/RTDMI and the Capture Client endpoint solutions.