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

The Hildacrypt 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%\ TXT
    • Instruction for recovery
  • %App.path%\ [Name]. HILDA!

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

The ransomware encrypts all the files and appends the [.HILDA!]  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.

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

• GAV: Hildacrypt.RSM (Trojan)

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