## CryptoDB

### Paper: On the Security of a Group Signature Scheme with Strong Separability

Authors: Lihua Liu Zhengjun Cao URL: http://eprint.iacr.org/2005/041 Search ePrint Search Google A group signature scheme allows a group member of a given group to sign messages on behalf of the group in an anonymous and unlinkable fashion. In case of a dispute, however, a designated group manager can reveal the signer of a valid group signature. Many applications of group signatures require that the group manager can be split into a membership manager and a revocation manager. Such a group signature scheme with strong separability was proposed in paper [1]. Unfortunately, the scheme is insecure which has been shown in [2][3][4]. In this paper we show that the scheme is untraceable by a simple and direct attack. Besides, we show its universal forgeability by a general attack which only needs to choose five random numbers. We minutely explain the technique to shun the challenge in the scheme.
##### BibTeX
@misc{eprint-2005-12379,
title={On the Security of a Group Signature Scheme with Strong Separability},
booktitle={IACR Eprint archive},
keywords={cryptographic protocols / Group signature, Untraceability,Universal forgeability.},
url={http://eprint.iacr.org/2005/041},
note={ zjcamss@hotmail.com 12830 received 15 Feb 2005},
author={Lihua Liu and Zhengjun Cao},
year=2005
}