Exploiting Small Leakages in Masks to Turn a Second-Order Attack into a First-Order Attack and Improved Rotating Substitution Box Masking with Linear Code Cosets.
Masking countermeasures, used to thwart side-channel attacks, have been shown to be vulnerable to mask-extraction attacks. State-of-the-art mask-extraction attacks on the Advanced Encryption Standard (AES) algorithm target S-Box recomputation schemes but have not been applied to scenarios where S-Boxes are precomputed offline. We propose an attack targeting precomputed S-Boxes stored in nonvolatile memory. Our attack targets AES implemented in software protected by a low entropy masking scheme and recovers the masks with 91% success rate. Recovering the secret key requires fewer power traces (in fact, by at least two orders of magnitude) compared to a classical second-order attack. Moreover, we show that this attack remains viable in a noisy environment or with a reduced number of leakage points. Eventually, we specify a method to enhance the countermeasure by selecting a suitable coset of the masks set.
New York University, New York, NY 10012, USA.
Alexander
A
DeTrano
Rutgers University, New Brunswick, NJ 08901, USA.
Naghmeh
N
Karimi
New York University, New York, NY 10012, USA.
Ramesh
R
Karri
Security Center of Excellence, Intel Corporation, Hillsboro, OR 97124, USA.
Xiaofei
X
Guo
Paris 8 University, 93526 Saint-Denis, France.
Claude
C
Carlet
Télécom ParisTech, 75634 Paris, France ; Secure-IC S.A.S., 35510 Cesson-Sévigné, France.
Sylvain
S
Guilley