Cryptology ePrint Archive: Report 2009/192

Linkability of Blind Signature Schemes over Braid Groups

Manoj Kumar

Abstract: Blindness and unforgeability are two essential security requirements of a secure blind signature scheme. Blindness means that after interacting with various users, the signer can never be able to link a valid message pair. Blindness is meaningless if after interacting with various users, the signer is able to link a valid message signature pair. This security vulnerability is known as linkability attack. Recently, Verma proposed two blind signature schemes over braid groups. Verma claimed that the proposed schemes are secure against all possible security vulnerabilities and also satisfy all essential securities properties.This paper reviews Verma’s proposed blind signature schemes and found that these scheme do not withstand against the linkability vulnerability.

Category / Keywords: applications / public-key cryptography, Blind signature , linkability, blindness, braid groups

Date: received 4 May 2009

Contact author: yamu_balyan at yahoo co in

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

Version: 20090504:212313 (All versions of this report)

Short URL: ia.cr/2009/192

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