W32/Sdbot-DFQ

Please follow the instructions for removing worms.

W32/Sdbot-DFQ is a worm with backdoor functionality for the Windows platform.

W32/Sdbot-DFQ 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.

W32/Sdbot-DFQ includes functionality to access the internet and communicate with a remote server via HTTP.

When first run W32/Sdbot-DFQ copies itself to <Windows>\ntvdm.exe.

The file ntvdm.exe is registered as a new system driver service named "NTVDM.", with a display name of "NTVDM." and a startup type of automatic, so that it is started automatically during system startup. Registry entries are created under:

HKLM\SYSTEM\CurrentControlSet\Services\NTVDM.

The following registry entries are set, disabling system software:

HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System
DisableTaskMgr
1

HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System
DisableRegistryTools
1

W32/Sdbot-DFQ sets the following registry entries, disabling the automatic startup of other software:

HKLM\SYSTEM\CurrentControlSet\Services\Messenger
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\RemoteRegistry
Start
4

HKLM\SYSTEM\CurrentControlSet\Services\TlntSvr
Start
4

Registry entries are set as follows:

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
SFCScan
0

HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\DomainProfile
EnableFirewall
0

HKLM\SOFTWARE\Policies\Microsoft\WindowsFirewall\StandardProfile
EnableFirewall
0

HKLM\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate
DoNotAllowXPSP2
1

HKLM\SOFTWARE\Microsoft\Ole
EnableDCOM
N

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
SFCDisable
ffffff9d

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
Shell
Explorer.exe %WINDIR%\ntvdm.exe

Registry entries are created under:

HKLM\SOFTWARE\Microsoft\Security Center
HKLM\SOFTWARE\Symantec\LiveUpdate Admin