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  3. W32.Seswol.B


Risk Level 1: Very Low

March 19, 2013
March 20, 2013 11:43:41 PM
Infection Length:
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Server 2008, Windows Vista, Windows XP
W32.Seswol.B is a worm that spreads through removable drives and encrypts certain files on the compromised computer.

Note: Virus definitions dated March 20, 2013 or earlier detect this threat as W32.Arseefour.

Antivirus Protection Dates

  • Initial Rapid Release version March 19, 2013 revision 008
  • Latest Rapid Release version April 25, 2013 revision 004
  • Initial Daily Certified version March 19, 2013 revision 018
  • Latest Daily Certified version April 25, 2013 revision 009
  • Initial Weekly Certified release date March 20, 2013
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
  • Modifies Files: Encrypts certain files on the compromised computer.


  • 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: Liang Yuan

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