Completely stealthy attacks on cyber-physical system with parity space based monitoring

The parity space approach is one of the most established model-based fault detection methods. The main purpose of this paper is to analyze the parity space-based fault detection monitoring system from the cyber security viewpoint considering an attack on the actuator channel. It is shown that under certain conditions a cyber attack can bypass the fault detection system based on the parity space approach without being detected. This weakness may be used by an adversary to conduct a cyber attack and remain undetected. Conditions of existence of a completely stealthy cyber attack are provided in the paper. Moreover, suggestions are given for a system developer to avoid completely stealthy attacks. An illustrative example is given to demonstrate the main results.