Abstract: The Schnorr signature scheme is a digital signature scheme based on discrete logarithms. Recently some attacks against the Schnorr signature scheme were presented in the literature and they claimed that these new attacks had the greater success probability. However, these attacks were analyzed and the conclusion is that all these new attacks are essentially trivial exhaust search ones. Given certain system security parameters, the success tacks is negligible. Moreover, some mistakes in the probability analysis of these attacks were probability of theses at pointed out.

Key words: Schnorr signature,Cryptanalysis,Exhaust search attack