Cryptanalysis of strong designated verifier signature scheme
Hongzhen Du · Computer Engineering and Applications Journal · 2011
Security analyses of an identity-based designated verifier signature scheme presented by Li Mingxiang et al. are given.It is found that the scheme exists two vital security flaws:the scheme is universal forgeable.And the scheme is not a strong designated verifier signature scheme since a non-designated-verifier can also check the validity of signatures.An improved scheme is proposed.This scheme overcomes the security flaws of the original scheme,improves the security of the system,and retains some merits of the original scheme.