The Security and Trust of Software Systems group, led by Prof. Dr. Sjouke Mauw, is looking for outstanding

master students who want to develop their master thesis within our group. Project description Like the air we breath, wireless channels are intangible and openly accessible, which make them a convenient communi-cation means. These features, however, increment the likelihood and severity of various security threats. Outstanding examples are mafia and distance fraud; two attacks proposed in 1988 [3] and 1993 [2], respectively, that were brought back to popularity in 2005 [4] thanks to the worldwide adoption of the RFID technology. Mafia fraud, sometimes called relay attack, is a man-in-the-middle attack where the adversary actively participates in an authentication protocol by relaying messages between two parties, making them believe that they have a direct communication. This attack can easily break a proximity claim that appears in many cryptographic applications and standardized contactless interfaces, such as ISO 14443, ISO 15693, and ISO 18092. Physical proximity is indeed a common requirement in access control policies in the physical world. One normally expects someone to be present when opening a door or turning on a car. In practice, the very design of many access control mechanisms enforces physical proximity naturally, e.g., mechanic locks or biometric identification. In wireless systems, however, providing the same kind of guarantee is far from being trivial. The most reliable approach to proximity checking in wireless systems is distance bounding, that is, a cryptographic protocol where the propagatio