Security Analysis of Improved EDHOC Protocol

Ephemeral Diffie-Hellman Over COSE (EDHOC) aims at being a very compact and lightweight authenticated key exchange with ephemeral keys. It is expected to provide mutual authentication, forward secrecy, identity protection, 128-bit security level. A formal analysis has already been proposed SECRYPT ’21, on former version, leading some improvements, in the ongoing evaluation process by IETF. Unfortunately, while can detect vulnerabilities protocol, it cannot evaluate actual In this paper, we study protocol as appeared version 15. Without complete breaks, anyway exhibit attacks $$2^{64}$$ operations, which contradict We thereafter propose of them no additional cost, achieve for all properties (i.e. privacy, identity-protection).