Threat Description



Aliases: Backdoor:W32/SdBot
Category: Malware
Type: Backdoor
Platform: W32


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.

More scanning & removal options

More information on scanning or removal options is available in the documentation for your F-Secure security product on the Downloads section of our Home - Global site.

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

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.


Suspect a file or URL was wrongly detected? Submit a sample to our Labs for analysis

Submit Now

Give And Get Advice

Give advice. Get advice. Share the knowledge on our free discussion forum.

Learn More