Covert Coordinated Attack Detection and Isolation Schemes for Cooperative Adaptive Cruise Control Systems

Cooperative adaptive cruise control (CACC) systems face critical cybersecurity challenges due to vulnerabilities in vehicle-to-vehicle (V2V) networks and onboard sensors. Covert attacks have become a critical research focus in CACC systems due to their inherent risks and stealthiness. In this article, a novel attack model called covert coordinated attack (CCA) is proposed, and its detection and isolation schemes are proposed to enhance the resilience of CACC systems against such an attack. First, the specific CCA strategies are proposed by revealing dual-channel attack coordination mechanisms targeting both sensors and V2V networks. Second, the detection framework based on unknown input observers (UIOs) is designed by monitoring the residual-based health characteristic. Third, based on the established two auxiliary systems, an attack isolation strategy integrating UIOs and extended state observers (ESOs) is proposed for attack reconstruction and system performance recovery. Finally, numerical simulations are conducted to validate both the stealthiness of CCA and the effectiveness of the proposed attack detection and isolation methods.