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

TL;DR

This paper introduces a new framework for modeling cyber-physical system attacks using constrained switching systems, enabling quantification of safety degradation due to cyber-attacks.

Contribution

It develops a novel modeling approach that integrates physical dynamics, attack patterns, and detection schemes within a unified constrained switching system framework.

Findings

Computed maximal safe sets under attack scenarios

Quantified safety degradation with new impact metrics

Validated approach with illustrative examples

Abstract

We propose a novel framework for modelling 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 the analysis of hybrid automata, and, specifically, constrained switching systems. Moreover, we use the developed models to compute the impact of cyber attacks on the safety properties of the system. In particular, we characterise system safety as an asymptotic property, by calculating the maximal safe set. The resulting new impact metrics intuitively quantify the degradation of safety under attack. We showcase our results via illustrative examples.