RANSOM_CRYPHERBST.A
Trojan-Ransom.MSIL.Agent.gfo (Kaspersky); Trojan.Cryptolocker (Symantec); W32/Herbst.A!tr (Fortinet)
Windows
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
TECHNICAL DETAILS
Arrival Details
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Other Details
This Trojan does the following:
- It encrypts all files in the following directory:
- %Desktop%\{All Files}
- %Desktop%\{Any Folder}\{All Files}
- %User Profile%\My Documents\My Pictures -> on Windows 2000, XP, and Server 2003
- %User Profile%\My Documents\My Music -> on Windows 2000, XP, and Server 2003
- %User Profile%\Pictures -> on Windows Vista and 7
- %User Profile%\Music -> on Windows Vista and 7
(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)
NOTES:
This ransomware has the following ransom note:
![](http://documents.trendmicro.com/images/RANSOM_CRYPHERBST_A1.jpg)
SOLUTION
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Remove the malware/grayware file that dropped/downloaded RANSOM_CRYPHERBST.A. (Note: Please skip this step if the threat(s) listed below have already been removed.)
Step 4
Scan your computer with your Trend Micro product to delete files detected as RANSOM_CRYPHERBST.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Step 5
Restore encrypted files from backup.
Did this description help? Tell us how we did.