Troj/Haxdoor-AF

Please follow the instructions for removing Trojans.

Troj/Haxdoor-AF is a backdoor Trojan which allows a remote intruder to gain access and control over the computer.

Troj/Haxdoor-AF includes functionality to:

- stealth its files, processes, registry entries and services
- prevent itself being terminated
- prevent itself being deleted
- disable other software, including anti-virus, firewall and security related applications

When Troj/Haxdoor-AF is installed the following files are created:

<System>\cz.dll
<System>\drct16.dll
<System>\hz.sys
<System>\p2.in
<System>\vdmt16.sys
<System>\winlow.sys
<System>\wz.sys

The files cz.dll, drct16.dll, winlow.sys and wz.sys are detected as Troj/Haxdoor-CN and the files hz.sys and vdmt16.sys are detected as Troj/Haxdoor-AF. The file p2.ini is a clean log file and may be deleted.

The following registry entries are created to run code exported by drct16.dll on startup:

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\drct16
DllName
drct16.dll

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\drct16
Startup
MeMessager

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\drct16
Impersonate
1

The file vdmt16.sys is registered as a new system driver service named "vdmt16", with a display name of "VIRTwin". Registry entries are created under:

HKLM\SYSTEM\CurrentControlSet\Services\vdmt16\

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

HKLM\SYSTEM\CurrentControlSet\Services\winlow\

Sophos's anti-virus products include Genotype ™ detection technology, which can proactively protect against new threats without requiring an update. Sophos customers have been protected against components of Troj/Haxdoor-AF (detected as Troj/Haxdoor-Fam) since version 3.93.