摘要：

针对张有谊等人提出的能抗合谋攻击的门限签名方案(计算机应用与软件，2008年12期)，给出一种伪造攻击方法，任何人都可以用该方法生成有效的门限签名，从而证明该方案是不安全的。针对其存在的缺陷，提出一个改进的门限签名方案，通过理论分析证明了改进方案的正确性和安全性。

关键词: 门限签名, 合谋攻击, 伪造攻击

Abstract:

This paper presents a forgery attack on the threshold signature scheme proposed by Zhang Youyi et al that can resist conspiracy attack. Everyone can generate a valid threshold signature, which proves the scheme is not secure. So an improved scheme is proposed to overcome the weakness of the signature scheme, and its validity and security are proved.

Key words: threshold signature, conspiracy attack, forgery attack

中图分类号: 

• TP309.2