- 14 September 2000
- 13 February 2007
VBS.Disabled.Worm is a script worm that is similar in function to VBS.NewLove.Worm. It uses Microsoft Outlook to send itself. Upon execution, it deletes all files from your hard drive except for files in the root directory. The body of the email message is in French.
Antivirus Protection Dates
- Initial Rapid Release version 14 September 2000
- Latest Rapid Release version 28 September 2010 revision 054
- Initial Daily Certified version 14 September 2000
- Latest Daily Certified version 28 September 2010 revision 036
- Initial Weekly Certified release date pending
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
This worm arrives as an attachment named Update.vbs. When executed, it copies itself to C:\Windows\System\Update.vbs. It then modifies the Windows Registry to run itself on startup by adding itself to the following registry key:
The worm creates a file called C:\Testfile.txt in which it stores email addresses. It does this by searching your hard drive for files with the following extensions: .wab, .txt, .htm, and .html. If it finds files with these extensions, it opens them and searches for email addresses. If it finds addresses within the open file, it copies them to C:\Testfile.txt.
When finished, the worm sends itself to the list of addresses in C:\Testfile.txt. It deletes all files on the system unless there is a file named 13a0.txt in the root of drive C. If this file exists, the message VIRUS 13à0 DISABLED appears and the worm does not execute its payload.
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.
Scan with Norton AntiVirus and delete files that are detected as VBS.Disabled.Worm. Remove the file Update.vbs and its full path from the
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run registry key. Replace any files that were deleted from your hard drive by the worm.