Cryptanalysis of tripartite and multi-party authenticated key agreement protocols

Al-Riyami and Paterson proposed four authenticated tripartite key agreement protocols which make use of the Weil pairing. Recently, Lee et al. extended the protocols to a multi-party setting assuming the existence of cryptographic multilinear forms. In this paper we show that the tripartite and multi-party authenticated key agreement protocols are insecure against several active attacks.