Dictionary Attack on Functional Transform-Based Cancelable Fingerprint Templates
Recently, Ratha and others proposed a cancelable biometrics scheme which transforms an original fingerprint template into a new one using a noninvertible transformation. However, the authors show that the original template is recovered by a dictionary attack if two transformed templates originating from it are revealed. In their attack, they simulate the transformation and construct a set of possible pre-images for each transformed template. Then, they find the correct preimage by computing the intersection of these sets. They present an algorithm implementing this idea as well as successful experimental results.