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The Design Space of Metamorphic Malware

A design space is presented for metamorphic malware. Metamorphic malware is the class of malicious self-replicating programs that are able to transform their own code when replicating. The raison d'etre for metamorphism is to evade recognition by malware scanners; the transformations are meant to defeat analysis and decrease the number of constant patterns that may be used for recognition. Unlike prior treatments, the design space is organized according to the malware author's goals, options, and implications of design choice. The advantage of this design space structure is that it highlights forces acting on the malware author, which should help predict future developments in metamorphic engines and thus enable a proactive defence response from the community. In addition, the analysis provides effective nomenclature for classifying and comparing malware and scanners.