What is cryptovirology?
Cryptovirology is the study of the applications of cryptography to malicious software [Yo95,YY96a]. It is an investigation into how modern cryptographic paradigms and tools can be used to strengthen, improve, and develop new malicious software (malware) attacks. Cryptovirology attacks have been devised to: give malware enhanced privacy and be more robust against reverse-engineering, give the attacker enhanced anonymity when communicating with deployed malware (e.g., over public bulletin boards and Usenet newsgroups [YY96a,YY97a]), improve the ability to steal data, improve the ability to carry out extortion, enable new types of denial-of-service, enable fault-tolerance in distributed cryptoviral attacks, and so on. Also, recent work shows how a worm can install a back door on each infected system that opens only when the worm is presented with a system-specific ticket that is generated by the worm’s author. This is called an access-for-sale worm [SS03b]. Cryptography has traditionally
