Wang Gui-lin pointed out two security limits of LHL threshold group signature scheme:the existence of signature forgery attack and the failure to possess anonymity and traceability at the same time.

• 本文针对王贵林等指出LHL签名方案的两个安全缺陷:不具有可验证性,导致签名的可伪造;不能同时具备匿名性和可追查性[2],提出了一种改进的方案。