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  3. MSIL.Yakizake


Risk Level 1: Very Low

September 26, 2007
September 27, 2007 12:03:32 AM
Infection Length:
10,752 bytes
Systems Affected:
Linux, Solaris, Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Vista, Windows XP
MSIL.Yakizake is a mass-mailing worm that runs within the .NET or Mono framework and requires that Thunderbird is installed.

Antivirus Protection Dates

  • Initial Rapid Release version September 26, 2007 revision 036
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version September 27, 2007 revision 002
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date October 3, 2007
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: Low
  • Large Scale E-mailing: Sends email to every address in the Thunderbird address book.


  • Distribution Level: Low
Note: On May 14, 2015, modifications will be made to the threat write-ups to streamline the content. The Threat Assessment section will no longer be published as this section is no longer relevant to today's threat landscape. The Risk Level will continue to be the main threat risk assessment indicator.
Writeup By: Peter Ferrie

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