WORM_VOBFUS.DH

This worm arrives by connecting affected removable drives to a system. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

Arrival Details

This worm arrives by connecting affected removable drives to a system.

It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This worm drops the following copies of itself into the affected system:

• %User Profile%\{random}.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Autostart Technique

This worm adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%User Profile%\{random}.exe /O"

Other System Modifications

This worm adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\WindowsUpdate\
AU
NoAutoUpdate = "1"

It modifies the following registry entries to hide files with Hidden attributes:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"

(Note: The default value data of the said registry entry is 1.)

Propagation

This worm drops the following copy(ies) of itself in all removable drives:

• Passwords.exe
• Porn.exe
• {random}.exe
• Secret.exe
• Sexy.exe

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

{garbage characters}
[autorun]
iCON={random}.exe,0
{garbage characters}
open={random}.eXe
{garbage characters}
acTioN=16375
{garbage characters}
uSeauTOplay=1
{garbage characters}

Download Routine

This worm downloads updated copies of itself from the following websites:

• http://{BLOCKED}u/m/3532.exe
• http://{BLOCKED}u/m/a371.exe

Other Details

This worm connects to the following possibly malicious URL:

• http://{BLOCKED}te.ftp21.net:34511/a/
• http://{BLOCKED}x.wiggy.me:34511/a.php

NOTES:
It also drops the following non-malicious file in removable drives:

• x.mpeg