On the Security of the Wireless Electric Vehicle Charging Communication

The adoption of fully Electric Vehicles (EVs) is happening at a rapid pace. To make the charging as fast and convenient as possible, new charging approaches are developed constantly. One such approach is wireless charging, also known as Wireless Power Transfer (WPT). Instead of charging an EV via a charging cable, the battery is charged wirelessly. For safety and efficiency reasons, the vehicle and the charging station continuously exchange critical information about the charging process. This includes, e.g., the maximum voltage and current, battery temperature, and State of Charge (SoC). Since there is no physical connection between the vehicle and the charging station, this necessary control communication has to be implemented as a wireless connection. However, if the communication is interrupted, the charging process is aborted for safety reasons. In this paper, we analyze the attack surface of EV charging standards that use such a wireless control communication. More specifically, we discuss potential wireless attacks that can violate the availability and analyze the implemented security features of a real-world wireless charging station that has already been deployed. We found that the tested charging station does not implement even simple security measures, such as IEEE 802.11w, that can protect the communication from denial-of-service attacks. Finally, we discuss potential countermeasures, and give recommendations to improve the security and increase the resilience of wireless charging.