Correlation power analysis (CPA) combined with genetic algorithms (GA) now achieves greater attack efficiency and can recover all subkeys simultaneously. However, two issues in GA-based CPA still need to be addressed: key degeneration and slow evolution within populations. These challenges significantly hinder key recovery efforts. This paper proposes a screening correlation power analysis framework combined with a genetic algorithm, named SFGA-CPA, to address these issues. SFGA-CPA introduces three operations designed to exploit CPA characteristics: propagative operation, constrained crossover, and constrained mutation. Firstly, the propagative operation accelerates population evolution by maximizing the number of correct bytes in each individual. Secondly, the constrained crossover and mutation operations effectively address key degeneration by preventing the compromise of correct bytes. Finally, an intelligent search method is proposed to identify optimal parameters, further improving attack efficiency. Experiments were conducted on both simulated environments and real power traces collected from the SAKURA-G platform. In the case of simulation, SFGA-CPA reduces the number of traces by 27.3% and 60% compared to CPA based on multiple screening methods (MS-CPA) and CPA based on simple GA method (SGA-CPA) when the success rate reaches 90%. Moreover, real experimental results on the SAKURA-G platform demonstrate that our approach outperforms other methods.

The Inner Product Masking (IPM) scheme has been shown to provide higher theoretical security guarantees than the Boolean Masking (BM). This scheme aims to increase the algebraic complexity of the coding to achieve a higher level of security. Some previous work unfolds when certain (adversarial and implementation) conditions are met, and we seek to complement these investigations by understanding what happens when these conditions deviate from their expected behaviour. In this paper, we investigate the security characteristics of IPM under different conditions. In adversarial condition, the security properties of first-order IPMs obtained through parametric characterization are preserved in the face of univariate and bivariate attacks. In implementation condition, we construct two new polynomial leakage functions to observe the nonlinear leakage of the IPM and connect the security order amplification to the nonlinear function. We observe that the security of IPM is affected by the degree and the linear component in the leakage function. In addition, the comparison experiments from the coefficients, signal-to-noise ratio (SNR) and the public parameter show that the security properties of the IPM are highly implementation-dependent.