Defense against Insider Threat: a Framework for Gathering Goal-based Requirements

Insider threat is becoming comparable to outsider threat in frequency of security events. This is a very worrying situation, as insider attacks have a high probability of success because insiders have authorized access and legitimate privileges. As a result, organizations can suffer financial losses and damage to assets and to reputation. Despite their importance, insider threats are still not properly addressed by organizations. We contribute to reverse this situation by introducing a framework composed of a method and of supporting awareness deliverables. The method organizes the identification and assessment of insider threat risks from the perspective of the organization goal(s)/business mission. This method is supported by three deliverables. First, by attack strategies structured in four decomposition trees. Second, by a pattern of insider attack which reduces an insider attack step to six possible scenarios. Third, by a list of defense strategies which helps on the elicitation of requirements. The output of the method consists of goal-based requirements for the defense against insiders. Attack and defense strategies are collected from the literature and from organizational control principles.