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  3. W32.Mydoom.B@mm


Risk Level 1: Very Low

January 28, 2004
January 29, 2004 9:04:11 PM
Infection Length:
29184 and 6144 bytes
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP
W32.Mydoom.B@mm is an encrypted mass-mailing worm that arrives as an attachment with either a .exe, .scr, .cmd, .zip, or .pif extension. It also performs a denial of service attack on www.microsoft.com and allows unauthorized remote access to the compromised host.

Antivirus Protection Dates

  • Initial Rapid Release version January 28, 2004
  • Latest Rapid Release version November 17, 2011 revision 017
  • Initial Daily Certified version January 28, 2004
  • Latest Daily Certified version November 17, 2011 revision 018
  • Initial Weekly Certified release date January 28, 2004
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Threat Assessment


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


  • Damage Level: Medium
  • Payload: Attempt to perform a DoS attack on various web sites.
  • Large Scale E-mailing: Sends a mass mailing of itself.
  • Modifies Files: Modifies the hosts file to prevent access to certain Web sites.


  • Distribution Level: High
  • Subject of Email: Varies
  • Name of Attachment: Varies
  • Shared Drives: Copies itself to Kazaa download folder.
Writeup By: Scott Gettis

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