Securing Phone as a Key against Relay Attacks

Paul Staat, Kai Jansen, Christian Zenger, Chris­tof Paar

18th escar Europe: The World's Leading Automotive Cyber Security Conference, page 47-58, 2020.


The smartphone is a central aspect of our daily lives and has driven the shift towards ubiquitous connectivity. More recently, context aware wireless applications have enabled convenient end-user applications such as indoor localization, home automation, or access control. A respective example from the automotive sector is vehicular access using Phone as a Key (PaaK). Like previous vehicular access systems, PaaK must also be protected against unauthorized access. A relay station attack pursues the goal of decreasing the estimated distance between car and key fob (smartphone), granting an attacker access to the car.

In this paper, we discuss relay attacks in view of recent PaaK developments. In this context, we investigate two relay detection approaches from the literature and propose a novel hybrid approach towards relay attack mitigation.