A Weakness in Authenticated Encryption Schemes Based on Tseng et al.'s Schemes

Tseng et al. have introduced in 2003 an authenticated encryption scheme by using self-certified public keys. Based on this scheme several authors have proposed new signature schemes avoiding some attacks against the original proposal. In this paper we show that there is a weakness on all these schemes affecting both the authentication of the signer’s public key and the own security of the system. We propose a slight but necessary modification to these schemes in order to avoid that weakness.