Quantifying impact on safety from cyber-attacks on cyber-physical systems

We propose a novel framework for modeling attack scenarios in cyber-physical control systems: we represent a cyber-physical system as a constrained switching system, where a single model embeds the dynamics of the physical process, the attack patterns, and the attack detection schemes. We show that this is compatible with established results in hybrid automata, namely, constrained switching linear systems. The proposed attack modeling approach admits a large class of non-deterministic attack policies and enables the characterization of system safety as an asymptotic property. By calculating the maximal safe set, the resulting new impact metrics intuitively quantify the degradation of safety and the impact of cyber attacks on the safety properties of the system under attack. We showcase our results via an illustrative example.