W32.Lirva.A@mm

NOTE: Due to a decreased rate of submissions, Symantec Security Response has downgraded this threat from a Category 3 to a Category 2 as of February 28, 2003.

W32.Lirva.A is a mass-mailing worm that also spreads by IRC, ICQ, KaZaA, and open network shares. This worm attempts to terminate antivirus and firewall products. It also emails the cached Windows 95/98/Me dial-up networking passwords to the virus writer.

When Microsoft Outlook receives the worm, the worm takes advantage of a vulnerability that allows the attachment to auto-execute when you read or preview the email. Information on this vulnerability and a patch can be found at http://www.microsoft.com/technet/security/bulletin/MS01-020.asp.

If the day of the month is the 7th, 11th, or 24th, the worm will launch your Web browser to www.avril-lavigne.com and display a graphic animation on the Windows desktop.

Protection

• Initial Rapid Release version January 7, 2003
• Latest Rapid Release version June 26, 2009 revision 017
• Initial Daily Certified version January 7, 2003
• Latest Daily Certified version June 26, 2009 revision 016
• Initial Weekly Certified release date January 7, 2003

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

Threat Assessment

Wild

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

Damage

• Damage Level: Medium

Distribution

• Distribution Level: High