BitPaymer Ransomware actively spreading in the wild.

June 11, 2018

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

BitPaymer Ransomware encrypts the victims files with a strong encryption algorithm until the victim pays a fee to get them back.

Contents of the dropper for BitPaymer ransomware

Infection Cycle:

The Ransomware adds the following files to the system:

  • Malware.exe
    • %Temp%\[Random].cmd
      • executable Commands
    • %AppData%\Roaming\[Random].bin
      • Executable dropper File
    • %App.path%\ [File Name].readme_txt
      • Instruction for recovery

Once the computer is compromised, the Ransomware copies its own executable into %Appdata% folder runs the following commands:

The Ransomware encrypts all the files and appends the .Locked extension onto each encrypted file’s filename.

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

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: BitPaymer.RSM (Trojan)