VBS.SST@mm

SUMMARY

VBS.SST@mm is a VBS email worm that has been encoded using a virus creation kit. This worm arrives as an attachment named AnnaKournikova.jpg.vbs. When executed, the worm emails itself to everyone in your Microsoft Outlook address book. On January 26, the worm will attempt to direct your Web browser to an Internet address in The Netherlands, from where the worm appears to have originated.



The following information is for network administrators of corporate versions of Norton AntiVirus.

For corporate users, Symantec Technical Support recommends the following

1. Make sure virus definitions are most current.
2. Delete the email. Do not open the attachment.
3. Disable Windows Scripting to prevent VBS files, such as AnnaKournikova.JPEG.VBS, from executing. Filter attachments with a VBS extension.
   • Microsoft Exchange 2000 in VAPI mode can strip attachments by extension. Contact Microsoft for further information.
   • Microsoft Exchange Server also provides the ExMerge utility, which can be used to purge the Information Store of messages with a specified subject or attachment name. This can be very useful during a virus crisis. For more information, please see the following Microsoft Articles:
     • XADM: How to Remove a Message from Exchange by Using the ExMerge Utility -- articleID: Q260037
     • XADM: Some Questions and Answers About the ExMerge Utility -- articleID: Q265441
4. Outlook 2000 with the latest security update will not execute VBS attachments. Contact Microsoft for further information.
5. Norton AntiVirus for Microsoft Exchange (NAVMSE) can block attachments by extension when in VAPI mode. Make sure NAVMSE is at a current build. The following Symantec's Knowledge Base documents may be helpful:
   • How to delete email and its attachment with Norton AntiVirus for Microsoft Exchange
   • How to block email attachments based on the file name or extension of attached files
6. Norton AntiVirus for Email Gateways 2.0 installed, attachments with VBS extensions can be blocked. See the Administrator's Guide for details. The following Symantec Knowledge Base document may also be helpful:
   • How to block email based on the file name or extension of attached files
   • How to set up local routing for Norton AntiVirus for Gateways 2.1
   • How to block attachments by extension with Norton AntiVirus for Gateways
7. Norton AntiVirus for Firewalls 1.5 installed, attachments with VBS extensions can sometimes be blocked. See the Administrator's Guide for details. There are unknown environmental factors that prevent some installations from blocking VBS files. If it works at your site, it will work reliably. If VBS blocking does not work at your site, it will not work at all.

Antivirus Protection Dates

• Initial Rapid Release version February 12, 2001
• Latest Rapid Release version September 28, 2010 revision 054
• Initial Daily Certified version February 12, 2001
• Latest Daily Certified version September 28, 2010 revision 036
• Initial Weekly Certified release date February 12, 2001

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: More than 1000
• Number of Sites: More than 10
• Geographical Distribution: High
• Threat Containment: Easy
• Removal: Moderate

TECHNICAL DETAILS

When run, the worm creates the following registry key:

HKEY_CURRENT_USER\Software\OnTheFly

If the worm is run on January 26, it attempts to direct your Web browser to an Internet address in The Netherlands.

Next, it checks to see if the mass-mailing routine has been executed. If not, the worm emails everyone in your Microsoft Outlook address book and sets the following key value equal to "1" (this is equivalent to true):

HKEY_CURRENT_USER\Software\OnTheFly\mailed

This prevents the mail routine from running again.

The subject, body and attachment sent by the worm are as follows:

Subject:

Here you have, ;o)

Message body:

Hi:
Check This!

Attachment:

AnnaKournikova.jpg.vbs

The worm continues running, and if it is deleted, it attempts to recreate itself. Due to a bug in the code, the worm instead recreates itself as a zero-byte file.

Recommendations

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.

REMOVAL

Virus definitions dated February 12, 2001, or later will detect this worm. To remove VBS.SST@mm:

1. Run LiveUpdate to make sure that you have the most recent virus definitions.
2. Start Norton AntiVirus (NAV), and run a full system scan, making sure that NAV is set to scan all files.
3. If any files are detected as infected by VBS.SST@mm, click Delete
4. (Optional -- This is not necessary for the function of your system.) Delete the registry key that was added by the worm.
   

CAUTION: We strongly recommend that you back up the system registry before making any changes. Incorrect changes to the registry could result in permanent data loss or corrupted files. Please make sure you modify only the keys specified. Please see the document How to back up the Windows registry before proceeding.
1. Click Start, and click Run. The Run dialog box appears.
2. Type regedit and then click OK. The Registry Editor opens.
3. Navigate to and delete the following key:
   
   HKEY_CURRENT_USER\Software\OnTheFly
   
4. Exit the Registry Editor.