WORM_TUFIK.AG

This malware sends email to all recipients listed in the MS Outlook address book.

It also drops copies of itself in all drives and their subfolders. These dropped copies use the names of the folders located on the said parent folder for their file names.

This worm arrives as attachment to mass-mailed email messages. It may be unknowingly downloaded by a user while visiting malicious websites.

It uses the default Windows folder icon to trick users into opening the file. Double-clicking the file executes this malware.

It drops copies of itself in all drives. These dropped copies use the names of the folders located on the said drives for their file names.

Arrival Details

This worm arrives as attachment to mass-mailed email messages.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

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

• %WINDOWS%\Document.exe
• %WINDOWS%\WINDOWS.exe

It drops the following file(s)/component(s):

• {drive}:\Nethood.htm - detected as HTML_TRAXG.A
• {drive}:\folder.htt - detected as HTML_TRAXG.A
• %system root%\net.txt

It uses the default Windows folder icon to trick users into opening the file. Double-clicking the file executes this malware.

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
TempCom = {malware copy}.com

Other System Modifications

This worm adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Netlogon\Parameters
DynamicSiteName = Default-First-Site-Name

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Setup
KaV300XP = 0

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = 0

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
HideFileExt = 1

(Note: The default value data of the said registry entry is 0.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
CabinetState
FullPath = 1

(Note: The default value data of the said registry entry is 0.)

HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Explorer\CabinetState
FullPath = 1

(Note: The default value data of the said registry entry is 0.)

HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Explorer\Advanced
Hidden = 0

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

Propagation

This worm drops the following copies of itself in all physical and removable drives:

• Ghost.bat
• WINDOWS.exe

It drops copies of itself in all drives. These dropped copies use the names of the folders located on the said drives for their file names.

It composes messages as part of its spamming routine. The messages it sends has the following details:

From: {e-mail address of the infected user}
To: {e-mail address in the Outlook Address book}
Subject: ?????
Message body: ??????Document???????????????
Attachment: Document.exe

Dropping Routine

This worm sets the attributes of its dropped file(s) to the following:

• Hidden
• System
• Read Only

Other Details

This worm does the following:

• Performs various time checks that trigger other routines. This includes dropping copies of itself in the Startup folder and invoking the "net view" command to gather the shared resources in the network. The following URLs are also found in its body but are not referenced in its code.
  • http://{BLOCKED}03.51.net/but.cs
  • http://{BLOCKED}503.{BLOCKED}u.china.com/but.cs
• Drops a copy of itself as {random name}.com in any of the following folders in the %Windows% directory:
  • fonts
  • help
  • system
  • temp
• It also drops copies of itself in all the subfolders of available drives.