Fuzzy vault scheme for fingerprint verification: implementation, analysis and improvements

Abstract

Fuzzy vault is a well-known technique that is used in biometric authentication applications. This thesis handles the fuzzy vault scheme and improves it to strengthen against previously suggested attacks while analyzing the effects of these improvements on the performance. We compare the performances of two different methods used in the implementation of fuzzy vault, namely brute force and Reed Solomon decoding with fingerprint biometric data. We show that the locations of fake (chaff) points leak some valuable information and propose a new chaff point placement technique that prevents that information leakage. A novel method for chaff point creation that decreases the success rate of the brute force attack from 100% to less than 3.3% is also proposed in this work. Moreover, a special hash function that allows us to perform matching in the hash space which protects the biometric information against the 'correlation attack' is proposed. Security analysis of this method is also presented in this thesis. We implemented the scheme with and without the hash function to calculate false accept and false reject rates in different settings.