Threat description


Category: Malware
Type: Packed
Platform: W32


This program is packed using a packer program associated with numerous other malware.


Automatic action

Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.

More scanning & removal options

More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.

You may also refer to the Knowledge Base on the F-Secure Community site for more information.

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Technical Details

Packed:W32/Tibs.AB identifies packed files with similar functionality to Email-Worm:W32/Zhelatin. Tibs.AB files are usually downloaded by clicking malicious links in heavily spammed e-mail messages


On execution, the malware creates these files:

  • %windir%\system32\windev-[random_numbers].sys
  • %windir%\system32\windev-peers.ini

And then hides them.


A noticeable characteristic for this malware is that it tries to connect to a lot of predefined IP addresses using UDP. A text file is also dropped which contains a possible lists of clients for the worm's peer-to-peer network. The details for the peer names and access ports are encoded. Example of the text file:

 [config]  [local]  [peers]  61CBE5C404F4C715C809A8588F42950C=9A2542751EBF00  61CBE5C4CB3D735B77590054E92865F3=9A2542BB1EBF00  8024083AF066B98A86BF0B0BF1135EF7=55198859159800  80A32744A44A3359F3F4B39D19E8E32B=53258C841C4400 

The installed component has rootkit functionality that can enable its process to be hidden from unsuspecting users.

Registry Modifications

The malware sets these values:

  • HKLM\System\CurrentControlSet\Services\windev-[random_numbers] ImagePath = %systemdir%\windev-[random_numbers].sys

Note: Usually %systemdir% is C:\Windows\system32


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