两个无证书聚合签名方案的安全性分析

Security Analysis on Two Certificateless Aggregate Signature Schemes

张玉磊等人(2015)提出了两种无证书聚合签名方案,并证明其方案在随机预言机模型下是可证明安全的。该文分析张玉磊等人提出的两种方案的安全性,指出了第1种方案可以抵抗两类攻击者的攻击;第2种方案不能抵抗第1类攻击者和第2类攻击者的攻击,给出详细的攻击过程,证明攻击者伪造出的签名可以通过验证,分析了第2种方案存在伪造攻击的原因,提出了改进的方案。

Zhang et al. （2015） proposed two certificateless aggregate signature schemes, and they demonstrated that both of their schemes are provably secure in the random oracle model. This paper analyzes the security of two schemes proposed by Zhang et al. and indicates that the first scheme can resist the attacks by Type 1 and Type 2 adversaries, and the second scheme can not resist the attacks by Type 1 and Type 2 adversaries. The study shows the processes of concrete forgery attacks, and proves the validity of the forged signature by attackers. The reasons of forgery attacks in the second scheme are analyzed, and the modified scheme is proposed.