Biblio

An approach to analyzing the security of a cyber-physical system (CPS) is proposed, where the behavior of a physical plant and its controller are captured in approximate models, and their interaction is rigorously checked to discover potential attacks that involve a varying number of compromised sensors and actuators. As a preliminary study, this approach has been applied to a fully functional water treatment testbed constructed at the Singapore University of Technology and Design. The analysis revealed previously unknown attacks that were confirmed to pose serious threats to the safety of the testbed, and suggests a number of research challenges and opportunities for applying a similar type of formal analysis to cyber-physical security.

Security attacks often exploit flaws that are not anticipated in an abstract design, but are introduced inadvertently when high-level interactions in the design are mapped to low-level behaviors in the supporting platform. This paper proposes a multi-representational approach to security analysis, where models capturing distinct (but possibly overlapping) views of a system are automatically composed in order to enable an end-to-end analysis. This approach allows the designer to incrementally explore the impact of design decisions on security, and discover attacks that span multiple layers of the system. This paper describes Poirot, a prototype implementation of the approach, and reports on our experience on applying Poirot to detect previously unknown security flaws in publicly deployed systems.