Serge Vaudenay

From ESC2017
Jump to: navigation, search

Title: Breaking the FF3 Format Preserving Encryption (Joint work with Betül Durak.)

Abstract: Last year, NIST published a standard for format preserving encryption including two algorithms: FF1 and FF3. We break FF3 by showing a known plaintext attack to recover the entire codebook with a data complexity better than the trivial attack. For that, we propose a new attack on 4-round Feistel networks to recover the round function tables.