W32/Sdbot-ACR

Please follow the instructions for removing worms.

You will also need to edit the following registry entries, if they are present. Please read the warning about editing the registry.

At the taskbar, click Start|Run. Type 'Regedit' and press Return. The registry editor opens.

Before you edit the registry, you should make a backup. On the 'Registry' menu, click 'Export Registry File'. In the 'Export range' panel, click 'All', then save your registry as Backup.

Locate the HKEY_LOCAL_MACHINE entries:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run

HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices

and remove any reference to any file you deleted.

Each user has a registry area named HKEY_USERS\[code number indicating user]\. For each user locate the entry:

HKU\[code number]\Software\Microsoft\Windows\
CurrentVersion\Run\

and remove any reference to any file you deleted.

Close the registry editor.

W32/Sdbot-ACR is a worm and IRC backdoor Trojan for the Windows platform.

W32/Sdbot-ACR spreads to other network computers infected with: Troj/Kuang, Troj/Sub7, Troj/NetDevil and W32/MyDoom.

W32/Sdbot-ACR runs continuously in the background, providing a backdoor server which allows a remote intruder to gain access and control over the computer via IRC channels.

When first run W32/Sdbot-ACR copies itself to <System>\yhn.exe and creates the file <System>\keylog.txt.

W32/Sdbot-ACR logs user keystrokes to <System>\keylog.txt. This file is not malicious and can simply be deleted.

The following registry entries are created to run yhn.exe on startup:

HKCU\Software\Microsoft\Windows\CurrentVersion\Run
Winamp Update
yhn.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Winamp Update
yhn.exe

HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
Winamp Update
yhn.exe