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  3. W32.Mytob@mm


Risk Level 2: Low

February 26, 2005
February 13, 2007 12:34:14 PM
Also Known As:
Win32.Mytob.B [Computer Associ, Mytob.A [F-Secure], Net-Worm.Win32.Mytob.a [Kasper, W32/Mydoom.bg@MM [McAfee], W32/Mytob-A [Sophos], WORM_MYTOB.A [Trend Micro]
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP

W32.Mytob.@mm is a mass-mailing worm that uses it own SMTP engine to send an email to addresses that it gathers from the Windows Address Book on the compromised computer. The worm also has the ability to open a back door and spread through the network by exploiting vulnerabilities.

Antivirus Protection Dates

  • Initial Rapid Release version February 26, 2005
  • Latest Rapid Release version May 4, 2015 revision 039
  • Initial Daily Certified version February 26, 2005 revision 002
  • Latest Daily Certified version May 4, 2015 revision 037
  • Initial Weekly Certified release date February 27, 2005
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: Moderate


  • Damage Level: Medium


  • 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: Takayoshi Nakayama

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