W32/Jaff.ED11!tr.ransom

Analysis

W32/Jaff.ED11!tr.ransom is a detection for a Ransomware Jaff trojan. Below are some of its observed characteristics/behaviours:

• This malware may drop any of the following file(s):
  
  • ReadMe.bmp : This file will be dropped all over the infected hosts and will serve as Ransom notes.
  • ReadMe.html : This file will be dropped all over the infected hosts and will serve as Ransom notes.
  • ReadMe.txt : This file will be dropped all over the infected hosts and will serve as Ransom notes.


• Affected files of this Ransomware will use the filenaming format {OriginalFileName.Ext}.jaff .


• This malware was also observed to affect/encrypt files located on USB or external drives.


• Below are illustrations of the malware's Ransom notes:
  

  Figure 1: ReadMe.txt.

  
  

  Figure 2: ReadMe.bmp.

  
  

  Figure 3: ReadMe.html.

  
  

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.