This chapter focuses on the security of automated vehicle platoons. Specifically, it examines the vulnerabilities that occur via disruptions of the information flows among the different types of sensors, the communications network and the control unit in each vehicle of a platoon. Multiple security domain nondeducibility is employed to determine whether or not the system can detect attacks. The information flows among the various domains provide insights into the vulnerabilities that exist in the system and whether the model is nondeducible. If nondeducibility is found to be true, then an attacker can create an undetectable attack. Defeating nondeducibility requires additional information sources, including invariants pertaining to vehicle platoon operation. A platoon is examined from the control unit perspective to determine if the vulnerabilities are associated with preventing situational awareness, which could lead to vehicle crashes.