WORM_VOBFUS.TR

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 file name}.exe
• %User Profile%\Passwords.exe
• %User Profile%\Porn.exe
• %User Profile%\Secret.exe
• %User Profile%\Sexy.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

It drops the following files:

• {drive letter}:\x.mpeg

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 file name}.exe = "%User Profile%\{random file name}.exe /{random character}"

Other System Modifications

This worm adds the following registry entries:

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

It modifies the following registry entries:

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:

• {drive letter}:\{random file name}.exe
• {drive letter}:\Passwords.exe
• {drive letter}:\Porn.exe
• {drive letter}:\Secret.exe
• {drive letter}:\Sexy.exe
• {drive letter}:\{folder name}.exe

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

NOTES:

It uses the filenames of files with the following extensions:

• .avi
• .bmp
• .doc
• .gif
• .jpe
• .jpg
• .mp3
• .mp4
• .mpg
• .pdf
• .png
• .tif
• .txt
• .wav
• .wma
• .wmv
• .xls

It then sets the attribute of the original folder to Hidden and System to trick users into thinking that the dropped copy is the legitimate folder.