Software Security Metrics for Malware Resilience

Abstract

We examine the level of resistance offered by a software product against malicious software (malware) attacks. Analysis is performed on the software architecture. This is available as a result of the software design process and can hence be used at an early stage in development. A model of a generic computer system is developed, based on the internationally recognized Common Criteria for Information Technology Security Evaluation. It is formally specified in the Z modeling language. Malicious software attacks and security mechanisms are captured by the model. A repository of generic attack methods is given and the concept of resistance classes introduced to distinguish different levels of protection. We assess how certain architectural properties and changes in system architecture affect the possible resistance classes of a product. This thesis has four main contributions: A generic model of an operating system from a security perspective, a repository of typical attack methods, a set of resistance classes, and an identification of software architecture metrics pertaining to ordered security levels.