Abstract: Aiming at the problems of large sampling amount and low utilization rate of attack information in single-point power analysis attack, a method of two-point joint power analysis attack for AES (Advanced Encryption Standard) is proposed. This method selects two power leakage points for power analysis according to the correlation between the power leakage points and the key in the AES. By constructing a power leakage model of intermediate variables, an intermediate value joint function is established which means, the method can be used to recover the key of AES. The simulation results demonstrate that the attack time of the two-point joint power analysis attack is reduced by 33.23% compared to two independent single-point power analysis attacks using 5 000 power curves, and the success rate of the two-point joint power analysis attack is significantly higher than that of the single-point power analysis attack with fewer power curve samples.

Key words: side-channel analysis, power analysis attack, Advanced Encryption Standard(AES), power leakage model, two-point joint attack