Analysis and improvement of a provable secure fuzzy identity-based signature scheme

To enjoy the property of error tolerance in the biometric identities extraction, the fuzzy identity-based signature has been initialized to issue a signature on behalf of a descriptive attributes set co instead of a single string. Any attributes set omega' can be used to verify the validity of the signature in case the distance between omega and omega' is less than a pre-defined threshold. Recently, Wang re-formalized the notion of fuzzy identity-based signature and proposed a concrete pairing-based construction along with the efficiency analysis and formal security proof. Unfortunately, by giving concrete attack, we indicate that Wang's scheme is not secure against forgery attack. We also present an improved scheme to prevent this attack.