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  3. W32.Shoho@mm


Risk Level 2: Low

December 20, 2001
February 13, 2007 11:46:56 AM
Also Known As:
I-Worm.Welyah, W32/Shoho.a@MM, W32/Shoho.b@MM, W32/Shoho.c@MM

W32.Shoho@MM is a mass mailing worm that is written in Visual Basic. It sends itself as the attachment "Readme.txt (many blank spaces) .pif"

This worm also uses the IFRAME vulnerability that allows Microsoft Outlook to execute the attachment automatically. There are three variants of this worm. All are detected as W32.Shoho@mm.

Antivirus Protection Dates

  • Initial Rapid Release version December 21, 2001
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version December 21, 2001
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date pending
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


  • Distribution Level: High
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: JP Duan

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