Polymorphic virus

Virus that re-encrypts itself with each infection

A polymorphic virus is one that encrypts its code differently with each infection, or generation of infections.

The aim of this behaviour is to make it difficult for anti-malware software to detect all files infected with the virus, requiring much more sophisticated detection techniques than simple file-infecting viruses, which insert their code unchanged into each infected file.

The same term is often also used to cover metamorphic viruses.

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SMI Oil and Gas Cyber Security 2014

Virus Bulletin
In this month's magazine:
  • VBSpam comparative review March 2014
  • VB100 comparative review on Ubuntu Server 12.04LTS
  • The shape of things to come
  • Threat intelligence sharing: tying one hand behind our backs
  • The curse of Necurs, part 1
  • More fast or more dirty?
  • Tofsee botnet
  • Back to VBA
  • Is the security industry up to the new challenges to come?
  • Greetz from academe: No place to Hyde
Virus Bulletin 04 2014
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