Cryptanalysis of Some Provably Secure Signature Schemes
一些可证安全签名方案的密码学分析

Recently,Okamoto and Victor K.Wei et al.proposed provably signature scheme in the standard model and two provably short signature schemes in the standard model respectively.In this paper,we show that the three schemes are all insecure against strong-key substitution attacks under the multi-user setting.In this attack,an adversary can generate a new public key satisfying legitimate signatures created by the legitimate signer.