Threat Description



Aliases:Backdoor:​W32/SdBot.CKF, Backdoor.Win32.SdBot.ebp


Backdoor:W32/SdBot.CKF is a backdoor. Backdoors are remote administration utilities that open infected machines to external control via the Internet or a local network. Upon execution, SdBot.CKF will attempt to connect to an IRC server and tries to download additional malware to the infected machine.


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.

Technical Details

Upon execution, SdBot.CKF will create a copy of itself in the following location:

  • %windir%\winudspm.exe

It creates the following registry entry to automatically start with Windows:

  • HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run Windows UDP Control = winudspm.exe

Once the backdoor is active, it connects to an IRC server, joins a certain channel and acts as a bot. The backdoor will try to contact the following IRC server:


Then it joins the following channels:

  • #blockbot2
  • #blockbot.msn

The malware attempts to download from the following locations:


The files are detected as follows:

  • dci.exe - Backdoor:W32/Rbot.GLP
  • is154890 - Trojan-Downloader.Win32.Agent.rcl
  • setup.exe - Backdoor:W32/IRCBot.GNS

Here are more commands used by the bot:

  • aim.stop
  • download
  • gone
  • l
  • lo
  • login
  • logout
  • msn.stop
  • r.getfile
  • r.upd4te
  • r.update
  • rm
  • rmzerm3b1tch
  • triton.stop
  • update

Furthermore, another sign of infection from this malware is an outbound connection to


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