Threat Explorer

The Threat Explorer is a comprehensive resource consumers can turn to for daily, accurate, up-to-date information on the latest threats, risks and vulnerabilities.

VBS.XPMsg@mm

VBS.XPMsg@mm

Discovered:
17 August 2001
Updated:
13 February 2007

VBS.XPMsg@mm is a simple Visual Basic Script (VBS) worm that sends email to all contacts in your Microsoft Outlook address book. It searches for all files that have extensions that begin with .ht; for example, .html, .hta, and .htm. It then copies itself to those files.

Antivirus Protection Dates

  • Initial Rapid Release version 17 August 2001
  • Latest Rapid Release version 28 September 2010 revision 054
  • Initial Daily Certified version 17 August 2001
  • 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 inserts itself into the body of every email message that it mails out. The message has the following characteristics:

Subject: Fw: Nude Pic

Message: There's some great links at  <pornographic website>. P.S. Don't tell the boss. :o)

NOTE: The worm does not use an attachment to spread. Microsoft Outlook messages have the capability to insert HTML code into the body of the email message. This is not an exploit in the same manner as Wscript.KakWorm, which has the ability to create a file from the email message. This worm does not use that exploit because it does not create a file.

It copy itself to all files (on all mapped and local drives) that have the .htm, .hta, .html file extensions.

After it has been mailed out, it creates the registry key

HKEY_CURRENT_USER\Software\Microsoft\VBS.XPMsg

with the value

VBS.XPMsg@mm

After it has finished its viral actions, it displays the message

You've been slammed by VBS/XPMsg@mm, a wonderful new work by FileSystemObject.
Office XP bites!  Get used to it!

VBS/XPMsg@mm is copyright (c) FileSystemObject, 2001
Thank you Microsoft!  What would this world be without you...


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.

Run LiveUpdate to make sure that you have the most recent virus definitions.
  1. Start Norton AntiVirus (NAV), and run a full system scan. Be sure that NAV is configured to scan all files.
  2. Delete all files that are detected as VBS.XPMsg@mm.


Writeup By: Douglas Knowles