Cryptology ePrint Archive: Report 2003/226

On the Security of a Group Signature Scheme with Forward Security

Guilin Wang

Abstract: 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 way. In case of a dispute, however, a designated group manager can reveal the signer of a valid group signature. Based on Song's forward-secure group signature schemes, Zhang, Wu, and Wang proposed a new group signature scheme with forward security at ICICS 2003. Their scheme is very efficient in both communication and computation aspects. Unfortunately, their scheme is insecure. In this paper we present a security analysis to show that their scheme is linkable, untraceable, and forgeable.

Category / Keywords: public-key cryptography / digital signature, group signature, forward security, cryptanalysis

Publication Info: Revised version appears in the Proc. of ICISC 2003, LNCS 2971, pp. 27-39. Springer-Verlag, 2004.

Date: received 30 Oct 2003, last revised 11 Apr 2004

Contact author: glwang at i2r a-star edu sg

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation

Version: 20040412:034445 (All versions of this report)

Short URL: ia.cr/2003/226

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