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  3. W95.Zperm.A


Risk Level 1: Very Low

February 13, 2007 11:50:42 AM

The W95.Zperm.A virus is one of the first metamorphic viruses for 32-bit Windows platforms. The virus does not use traditional polymrophic encryption. Rather, it mutates its code by using jump instruction insertion. The complete virus body is permutated including the permutation engine itself. A variant known as W95.Zperm.B is known to exist.

Antivirus Protection Dates

  • Initial Rapid Release version June 29, 2000
  • Latest Rapid Release version June 29, 2000
  • Initial Daily Certified version June 29, 2000
  • Latest Daily Certified version June 29, 2000
  • 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: Low
Writeup By: Peter Szor

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