MSIL/FilecoderTro.B4F8!tr.ransom

Analysis

MSIL/FilecoderTro.B4F8!tr.ransom is a detection for a Ransomware trojan.
Below are some of its observed characteristics/behaviours:

• Affected files of this Ransomware will keep the original file name and extension.


• This malware was also observed to affect/encrypt files located on shared drive within the same subnet.


• This malware may display the random twinkling and moving windows to disturb the victim desktop, below is an illustration of the capture:
  

  Figure 1: Displaying twinkling windows.

  
  
• Below is an illustration of the encryption codes:
  

  Figure 2: Encryption codes.

  
  

Recommended Action

• Make sure that your FortiGate/FortiClient system is using the latest AV database.
• Quarantine/delete files that are detected and replace infected files with clean backup copies.