Security Analysis of Two Group Signature Schemes
Pingshui Wang · Computer Technology and Development · 2007
Group signature schemes have many applications,such as electronic cash and electronic vote.Thus,it is significant to devise efficient and secure group signature schemes based on all kinds of mathematic problems.In this paper,a group signature scheme based on Chinese remainder theorem and a group signature scheme based on RSA signature scheme are studied.Two security flaws in these schemes are found:in the former,the modulus of the system can be decomposed by every member of the group,so the private keys of everyone in the group can be computed;in the latter,the opening algorithm of the group signature scheme is incorrect,so the signer of the group signature can not be traced correctly.The analysis shows that the two schemes are not secure and need to be implemented.