  Platoons of autonomous vehicles are being investigated as a way to increase
road capacity and fuel efficiency. Cooperative Adaptive Cruise Control (CACC)
is an approach to achieve such platoons, in which vehicles collaborate using
wireless communication. While this collaboration improves performance, it also
makes the vehicles vulnerable to cyber-attacks. In this paper the performance
of a sliding mode observer (SMO) based approach to cyber-attack detection is
analysed, considering simultaneous attacks on the communication and local
sensors. To this end, the considered cyber-attacks are divided into three
classes for which relevant theoretical properties are proven. Furthermore, the
harm that attacks within each of these classes can do to the system while
avoiding detection is analysed based on simulation examples.
