Printer Friendly Page

Discovered: May 08, 2000
Updated: February 13, 2007 11:56:25 AM
Also Known As: W32.Mypics.Worm
Type: Worm

W32.Mypics.Worm.36352 is a variant of the W32.Mypics.Worm . The worm propagates by automatically sending itself to as many as 50 people in the Outlook address book. The subject line is empty and the body of the email contains a worm installation program attachment named Mypics.exe. Mypics.exe extracts the files Mscomm32.ocx and Pictures.exe. Pictures.exe runs automatically and displays the following message:


It is important to note that the worm has been written using Microsoft Visual BASIC. For the worm to run, the file Msvbvm50.dll (a Visual BASIC Virtual Machine run-time library) must reside on the computer. This file does not propagate with the worm, so if this file is not on the computer the worm does not function.

Antivirus Protection Dates

  • Initial Rapid Release version May 11, 2000
  • Latest Rapid Release version January 18, 2008 revision 040
  • Initial Daily Certified version May 11, 2000
  • Latest Daily Certified version January 17, 2008 revision 033

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Writeup By: Edric Ta

Discovered: May 08, 2000
Updated: February 13, 2007 11:56:25 AM
Also Known As: W32.Mypics.Worm
Type: Worm

Norton AntiVirus detects this worm as W32.Mypics.Worm.36352. After Pictures.exe is executed, the worm remains resident in memory and monitors the system clock. When the worm detects the year 2000 (that is, January 1, 2000), the worm inserts and executes a file named Cbios.com. The worm also overwrites the Autoexec.bat file.

The Cbios.com file is a 15-byte program written in assembly and designed to overwrite the high byte of the two-byte CMOS checksum value in the system BIOS. As a result, the computer displays a system BIOS error, such as

CMOS Checksum Invalid

the next time the computer is cold started.

You can correct this by launching the system BIOS setup utility and saving the BIOS data again. This will rewrite and recalculate the BIOS checksum value.

The worm overwrites Autoexec.bat with the following data:

@Echo Off
echo y|format/q c: /v:Erased

The new Autoexec.bat file size becomes 41 bytes. As a result, when you boot the computer, drive C is formatted.


Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
  • Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
  • Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.

Writeup By: Edric Ta

Discovered: May 08, 2000
Updated: February 13, 2007 11:56:25 AM
Also Known As: W32.Mypics.Worm
Type: Worm

To remove this worm:

  1. End the Pictures.exe task by pressing Ctrl+Alt+Delete once. In the list, select "Pictures" and then click End Task.
  2. Remove the following registry entries:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunServices= C:\Pictures.exe
    HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Windows\RunServices= C:\Pictures.exe
  3. Check whether the Autoexec.bat file has been modified (this will only occur if the computer's system clock is set to year 2000). If so, delete Autoexec.bat and restore an original copy from backup.
  4. Check whether the Cbios.com file exists (this file will only exist if the computers system clock is set to year 2000). If so, delete the Cbios.com file.
  5. In the root of C:, look for the Picture.exe file and delete it.
  6. The worm alters the home page in the Microsoft Internet Explorer browser. You will need to restore the original home page.

Writeup By: Edric Ta