W32.Myparty @mm Virus

W32.Myparty@mm is a mass-mailing email worm. It has the following characteristics:
Subject: new photos from my party!
Message:
Hello!

My party... It was absolutely amazing!
I have attached my web page with new photos!
If you can please make color prints of my photos. Thanks!

Attachment: www.myparty.yahoo.com

The worm sends email to all contacts in your Windows address book, and to email addresses that if finds in the Outlook Express Inboxes and folders.

In addition, the worm sends a message to the author so that the author can track the worm.

On NT/2000/XP systems, the worm drops a backdoor Trojan that allows a hacker to control your system. NAV will detect this as Backdoor.Myparty.

Finally, if the file name of the worm is Access.<any extension>, it may launch your Web browser to http:/ /www.disney.com. However, the worm does not contain code which can generate a file with the name Access.<any extension>, so it is highly unlikely that this will trigger.

Also Known As: W32/Myparty@MM, WORM_MYPARTY.A, W32/MyParty-A, Win32.MyParty, I-Worm.Myparty

Type: Trojan Horse, Worm

Infection Length: 29,696 bytes

Virus Definitions: January 28, 2002

Threat Assessment:

 

Wild: Medium

Damage: Low

Distribution: High

Wild:

• Number of infections: More than 1000
• Number of sites: More than 10
• Geographical distribution: High
• Threat containment: Easy
• Removal: Easy

Damage:

• Payload Trigger: January 25-29, 2002
• Payload:
  • Large scale e-mailing: Sends email to all contacts in your Windows address book, and to email addresses that if finds in the Outlook Express Inboxes and folders.

Distribution:

• Subject of email: new photos from my party!
• Name of attachment: www.myparty.yahoo.com
• Size of attachment: 29,696 bytes

Technical description:

W32.Myparty@mm arrives as an email with the following characteristics:

Subject: new photos from my party!
Message:
Hello!

My party... It was absolutely amazing!
I have attached my web page with new photos!
If you can please make color prints of my photos. Thanks!

Attachment: www.myparty.yahoo.com

When it is executed, the worm first checks the date. If the computer date is not between January 25 to 29, 2002 or if the keyboard settings are set to Russian, the worm copies itself to:

C:\Recycled-F-<random digits>-<random digits>-<random digits>

and exits.

Otherwise, the worm continues.

The worm next checks its own file name, and performs different actions depending on the file name or extension:

• If the file name is "Access" the worm attempts to launch your Web browser to http:/ /www.disney.com and exits. However, the worm does not contain code which can generate a file with the name Access.<any extension>, so it is highly unlikely that this will trigger.
  
• If the file name has a .com extension, the worm copies itself to one of the following locations:
  
  • C:\Regctrl.exe (Windows NT/2000/XP)
  • C:\Recycled\Regctrl.exe (Windows 95/98/Me).
  
  and then executes the Regctrl.exe file.

• If the file name has a .exe extension such as Regctrl.exe, the worm begins its propagation routine:
  1. The worm searches the Windows address book that is used by Microsoft Outlook and Outlook Express, and through files with the extension .dbx in the Microsoft Outlook Express folder for email addresses. (The .dbx files are Microsoft Outlook Express folders and inboxes.)
  2. The worm sends itself to these email addresses using its own SMTP engine. The worm uses the default SMTP server address that is configured on the computer. The From: address is set to your email address.
  3. On Windows NT/2000/XP computers the worm creates a backdoor Trojan:
  
  %Windows%\Profiles\%User_name%\Start Menu\Programs\Startup\msstask.exe
  
  or
  
  \Documents and Settings\%User_name%\Start Menu\Programs\Startup\msstask.exe
  
  so that it is executed when you start Windows. This backdoor trojan contacts a Webpage at 209.151.250.170 which allows the author to have access to the computer. Depending on the contents of the Webpage, the backdoor will perform different actions.
  
  NOTES:
  • %Windows% is a variable. The worm locates the \Windows folder (by default this is C:\Windows or C:\Winnt) and copies itself to that location
  • %User_name% is a variable. The worm locates the name of the currently logged-on user, and uses that where indicated.

Removal instructions:

1. Run LiveUpdate to make sure that you have the most recent virus definitions.
2. Do one of the following, depending on your operating system:
• Windows 95/98/Me. Restart the computer in Safe mode. For instructions on how to do this, read the document How to restart Windows 9x or Windows Me in Safe Mode.
• Windows NT/2000/XP. End task in the Msstask.exe process. To do this:
  1. Press Ctrl+Alt+Delete one time.
  2. Click Task Manager.
  3. Click the Processes tab.
  4. Click the "Image Name" column header two times to sort the processes alphabetically.
  5. Scroll through the list and look for the following process:
  
  Msstask.exe
  
  CAUTION: This is not the same as Mstask.exe--note the single "s". Mstask.exe is a legitimate Microsoft process. Do not end task on it.
  
  6. If you find the file--you will only find it if the process is currently running--click it and then click End Process.
  7. Close the Task Manager.
3. Start Norton AntiVirus (NAV), and make sure that NAV is configured to scan all files. For instructions on how to do this, read the document How to configure Norton AntiVirus to scan all files.
4. Run a full system scan.
5. Delete all files that are detected as W32.Myparty@mm or Backdoor.Myparty.

Write-up by: Douglas Knowles and Eric Chien