Hardening Fingerprint Fuzzy Vault Using Password

Security of stored templates is a critical issue in biometric systems because biometric templates are non-revocable. Fuzzy vault is a cryptographic framework that enables secure template storage by binding the template with a uniformly random key. Though the fuzzy vault framework has proven security properties, it does not provide privacy-enhancing features such as revocability and protection against cross-matching across different biometric systems. Furthermore, non-uniform nature of biometric data can decrease the vault security. To overcome these limitations, we propose a scheme for hardening a fingerprint minutiae-based fuzzy vault using password. Benefits of the proposed password-based hardening technique include template revocability, prevention of cross-matching, enhanced vault security and a reduction in the False Accept Rate of the system without significantly affecting the False Reject Rate. Since the hardening scheme utilizes password only as an additional authentication factor (independent of the key used in the vault), the security provided by the fuzzy vault framework is not affected even when the password is compromised.