1. /
  2. Security Response/
  3. W32.Mytob.V@mm


Risk Level 2: Low

April 3, 2005
February 13, 2007 12:36:16 PM
Also Known As:
Win32.Mytob.AA [Computer Assoc, Net-Worm.Win32.Mytob.c [Kasper, W32/Mytob.c@MM [McAfee], W32/Mytob-C [Sophos], WORM_MYTOB.V [Trend Micro]
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP

W32.Mytob.V@mm is a mass-mailing worm that uses it own SMTP engine to send an email to addresses that it gathers from files on the compromised computer. The email has a variable subject and attachment name. The attachment will have a .bat, .cmd, .doc, .exe, .htm, .pif, .scr, .tmp, .txt, or .zip file extension.

The worm also has the ability to open a back door and spreads through the network by exploiting common system vulnerabilities.

Antivirus Protection Dates

  • Initial Rapid Release version April 4, 2005
  • Latest Rapid Release version August 20, 2008 revision 017
  • Initial Daily Certified version April 4, 2005
  • Latest Daily Certified version August 20, 2008 revision 016
  • Initial Weekly Certified release date April 6, 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: Candid Wueest

Search Threats

Search by name
Example: W32.Beagle.AG@mm
STAR Antimalware Protection Technologies
Internet Security Threat Report