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  3. W32.Pilleuz!gen


Risk Level 1: Very Low

September 29, 2009
December 7, 2009 6:01:23 AM
Also Known As:
Packed.Generic.255 [Symantec]
Trojan, Virus
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows Vista, Windows XP
W32.Pilleuz!gen is a heuristic detection for files that may have been obfuscated or encrypted in order to conceal them from antivirus software.

Note: Virus definitions dated December 5, 2009 or earlier detect this threat as Packed.Generic.255.

For more information, please read the following resources:
The Mariposa Butterfly
The Mariposa / Butterfly Bot Kit
Jailing the Butterfly

Antivirus Protection Dates

  • Initial Rapid Release version September 29, 2009 revision 051
  • Latest Rapid Release version December 5, 2009 revision 009
  • Initial Daily Certified version September 30, 2009 revision 002
  • Latest Daily Certified version December 5, 2009 revision 021
  • Initial Weekly Certified release date September 30, 2009
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

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