一个可转换限定验证人签名方案的安全缺陷(英文)

On Zhang et al.’s Convertible Limited Verifier Signature Scheme

最近,张键红等人提出一个可转换限定验证人签名方案,并且声称只有限定验证人才能把签名转换为一个普通的数字签名.本文指出在他们的方案中签名人不仅能向第三方证实或否认签名,而且也可以把签名转换为一个普通的数字签名.因此,他们的声称是不对的.

Recently, Zhang et al. proposed a convertible limited verifier signature scheme and claimed that only the limited verifier can independently convert the signature into an ordinary one. In this paper, we show that, in Zhang et al.＇s scheme, the signer not only can confirm or deny the signature, but also can independently convert the given signature into publicly verifiable one, and Zhang et al.＇s claim is hence incorrect.