  Reconfigurable intelligent surfaces (RIS) is considered as a revolutionary
technique to improve the wireless system performance by reconfiguring the radio
wave propagation environment artificially. Motivated by the potential of RIS in
vehicular networks, we analyze the secrecy outage performance of RIS-aided
vehicular communications in this paper. More specifically, two vehicular
communication scenarios are considered, i.e., a vehicular-to-vehicular (V2V)
communication where the RIS acts as a relay and a vehicular-to-infrastructure
(V2I) scenario where the RIS functions as the receiver. In both scenarios, a
passive eavesdropper is present attempting to retrieve the transmitted
information. Closed-form expressions for the secrecy outage probability (SOP)
are derived and verified. The results demonstrate the potential of improving
secrecy with the aid of RIS under both V2V and V2I communications.
