AnonMAKE: Toward Secure and Anonymous Mutually Authenticated Key Exchange Protocol for Vehicular Communications

Due to real-time data sharing in the Intelligent Transportation System (ITS), the automobile industry has evolved enormously in recent years. However, as more vehicles become connected, the peril of cyberattacks increases, necessitating safeguarding traffic safety-related data provided by individual vehicles and public transportation to avoid perilous situations and infringement of confidentiality. In this regard, a recent work (10.1109/TITS.2021.3099488) suggested an anonymous batch data authentication and key exchange protocol. This paper shows that the work lacks true anonymity during authentication, employs a session-independent key, and is prone to session key disclosure and replay attacks. Apart from cryptanalysis, we present a novel privacy-enhancing mutual authentication and key agreement protocol supporting batch authentication resisting comprehensive security attacks in the vehicular system, including traffic data replay, vehicle impersonation, and man-in-the-middle attacks. The suggested scheme achieves security correctness under formal BAN logic analysis and is safer against the STRIDE effect. The empirical performance estimation reveals that the novel approach under adequate security assumptions outperforms the state-of-the-art solutions by achieving about 20% higher security traits while lowering 15% authentication delay, consuming 15% less bandwidth, and increasing 44% storage efficiency. Thus, our protocol is more suitable for lightweight vehicular communications.