对一类群签名方案的伪造攻击

Forgery Attacks on a Series Group Signature Schemes

该文对王晓明等(2003)和林松等(2006)最近依据Tseng-Jan(1999)群签名方案各自提出的一种改进群签名设计了两种伪造攻击策略。利用该伪造攻击,攻击人不需要任何签名者的保密身份信息和秘密密钥信息,只是通过选取随机参数、改变原方案的部分设计步骤就能成功伪造出群成员证书,进而伪造出验证有效的群签名,从而威胁到群签名人的合法权益。该文的伪造攻击策略对Lee-Chang(1998)群签名、Tseng-Jan群签名及由其演化而来的所有群签名方案都具有效性,从而证明该类群签名方案全都是不安全的。

Two kinds of forgery attacks strategy on the group signature schemes proposed respectively by Wang et aL. （2003） and Linet al.. （2006） based on the Tseng-Jan＇s（1999） group signature scheme is developed. Without using any secret identification or secret key, anyone can forgery a valid group member certificate and then generate a valid group signature using the forged certificate only through selecting some random parameters and changing the calculation procedures. Moreover, this kind of forgery attacks strategy can be used in Lee-Chang＇s （1998） group signature scheme, Tseng-Jan＇s group signature scheme and their varietals＇. It means this series of group signature schemes is insecure.