Secret Key Leakage from Public Key Perturbation of DLP-Based Cryptosystems

Finding efficient countermeasures for cryptosystems against fault attacks is challenged by a constant discovery of flaws in designs. Even elements, such as public keys, that do not seem critical must be protected. From the attacks against RSA [5,4], we develop a new attack of DLP-based cryptosystems, built in addition on a lattice analysis [26] to recover DSA public keys from partially known nonces. Based on a realistic fault model, our attack only requires 16 faulty signatures to recover a 160-bit DSA secret key within a few minutes on a standard PC. These results significantly improves the previous public element fault attack in the context of DLP-based cryptosystems [22]. To Jean-Jacques, for his emeritus

• Type: Journal
• Year: 2012
• Where: BIRTHDAY
• Authors: Alexandre Berzati, Cécile Canovas-Dumas, Louis Goubin
• Keywords: Applied Computing, BIRTHDAY 2012, Dsa Public Keys, Fault Model, Lattice Analysis