Threat Description





A remote administration utility which bypasses normal security mechanisms to secretly control a program, computer or network.


Automatic action

Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.


You may wish to refer to the Support Community for further assistance. You also may also refer to General Removal Instructions for a general guide on alternative disinfection actions.

Eliminating a Local Network Outbreak

If the infection is in a local network, please follow the instructions on this webpage:

Technical Details

Backdoor:W32/SdBot comprises a large family of remote access utilities known to be used by hackers to gain unauthorized control of a user's computer system.

Variants in the SdBot family include:


Depending on the variant, SdBot backdoors copy themselves either to the Windows System directory, or to other directories located in the System directory. It also ensures the copy is started when the system stars by creating a subkey in one of the following registry keys:

  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunServices
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run

The name of subkey and its value differ depending on the variant.


SdBot backdoors connect to various IRC servers, joining an IRC channel (the choice of channel is hardcoded into the code) in order to receive instruction from the attacker(s). The backdoor can perform a variety of actions, including acting as an IRC proxy server, downloading and executing remote files, sending messages and more.


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