Scientific Publishing Ltd.
Today, the security of the information systems of public and private organizations is one of the top priorities of developers of Information Security Systems (ISS). ISS isn't only antivirus software, but also firewalls and IDS products. Each ISS developer aspires to create malware detection mechanisms that would more efficiently and promptly detect and neutralize viruses. In this paper, a signature-based selective mechanism in detecting virus signatures in executable files was found and investigated. A pattern under which the Microsoft Security Essentials antivirus software not detecting a virus signature deliberately placed in files was revealed.