This book constitutes the refereed proceedings of the 5th InternationalConference on Mathematical Methods, Models, and Architectures forComputer Network Security, MMM-ACNS 2010, held in St. Petersburg, Russiain September 2010.The 16 revised full papers and 6 revised short papers presented togetherwith 5 invited papers were carefully reviewed and selected from a totalof 54 submissions. The papers are organized in topical sections onsecurity modeling and covert channels, security policies and formalanalysis of security properties, authentication, authorization, accesscontrol and public key cryptography, intrusion and malware detection, security of multi-agent systems and software protection, as well as.adaptive security, security analysis and virtualization.