The importance of in-vehicle network security has increased with an increase in
automated and connected vehicles. Hence, many attacks and countermeasures have
been proposed to secure the controller area network (CAN), which is an existent
in-vehicle network protocol. At the same time, new protocols-such as FlexRay and
Ethernet-which are faster and more reliable than CAN have also been proposed.
European OEMs have adopted FlexRay as a control network that can perform the
fundamental functions of a vehicle. However, there are few studies regarding
FlexRay security. In particular, studies on attacks against FlexRay are limited
to theoretical studies or simulation-based experiments. Hence, the vulnerability
of FlexRay is unclear. Understanding this vulnerability is necessary for the
application of countermeasures and improving the security of future
vehicles.
In this article, we highlight the vulnerability of FlexRay found in the
experiments conducted on a real FlexRay network. Consequently, we clarify the
conditions under which attackers masquerade as legitimate electronic control
units (ECUs) and transmit spoofed FlexRay frames. We also confirm that a
consumer vehicle’s functions such as steering, braking, and acceleration can be
controlled maliciously using spoofing attacks. Furthermore, we discuss
countermeasures against spoofing attacks on FlexRay networks.
