Journal in Computer Virology

, Volume 2, Issue 3, pp 211–229 | Cite as

Hunting for metamorphic engines

  • Wing Wong
  • Mark StampEmail author
Original Paper


In this paper, we analyze several metamorphic virus generators. We define a similarity index and use it to precisely quantify the degree of metamorphism that each generator produces. Then we present a detector based on hidden Markov models and we consider a simpler detection method based on our similarity index. Both of these techniques detect all of the metamorphic viruses in our test set with extremely high accuracy. In addition, we show that popular commercial virus scanners do not detect the highly metamorphic virus variants in our test set.


Hide Markov Model Similarity Score Hide State Computer Virus Metamorphic Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag France 2006

Authors and Affiliations

  1. 1.Department of Computer ScienceSan José State UniversitySan JoséUSA

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