W32.Klez.D@mm

W32.Klez.D@mm is a modified variant of W32.Klez.A@mm. Most of the functionality remains the same. The virus that W32.Klez.A@mm carried, W32.Elkern.3326, is also carried and inserted on the system by this variant.

The worm exploits a vulnerability in Microsoft Outlook and Outlook Express in an attempt to execute itself when you open or even preview the message. Further information and a patch for the vulnerability can be found at

http://www.microsoft.com/technet/security/bulletin/MS01-020.asp

NOTES:

• Definitions dated November 8, 2001, detect this worm as W32.Klez.B@mm.
• Definitions dated prior to November 8, 2001, detect the virus that this variant inserts as W32.ElKern.3326.

For information about how Klez affects a Macintosh computer, read the document Are Macintoshes affected by the Klez virus?

Protection

• Initial Rapid Release version November 8, 2001
• Latest Rapid Release version November 8, 2001
• Initial Daily Certified version November 8, 2001
• Latest Daily Certified version November 8, 2001
• Initial Weekly Certified release date pending

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

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: 0 - 49
• Number of Sites: 0 - 2
• Geographical Distribution: Low
• Threat Containment: Easy
• Removal: Easy

Damage

• Damage Level: High

Distribution

• Distribution Level: Medium