Modeling and verification of insider threats using logical analysis

In this paper we combine formal modeling and analysis of infrastructures of organisations with sociological explanation to provide a framework for insider threat analysis. We use the Higher Order Logic proof assistant Isabelle/HOL to support this framework. In the formal model, we exhibit and use a common trick from the formal verification of security protocols showing that it is applicable to insider threats. We introduce briefly a three step process of social explanation illustrating that it can be applied fruitfully to the characterisation of insider threats. We introduce the Insider theory constructed in Isabelle that implements this process of social explanation. To validate that the social explanation is generally useful for the analysis of insider threats and to demonstrate our framework, we model and verify the insider threat patterns Entitled Independent and Ambitious Leader in our Isabelle/HOL framework