Make It Easy! Timing Leakage Analysis on Cryptographic Chips Based on Horizontal Leakage

Timing analysis presents a significant threat to cryptographic modules. However, traditional timing leakage analysis has notable limitations, especially when precise execution times cannot be obtained. In this paper, we propose a novel timing leakage analysis method that leverages horizontal leakage in the power/electromagnetic channel by detecting the trace length of encryption processes under varying inputs. To demonstrate the effectiveness of our approach, we conducted systematic experimental evaluations across a range of cryptographic devices. In comparison to timing leakage analysis based on plaintext-ciphertext correlation, our method offers higher accuracy at lower testing costs and exhibits improved resistance to vertical noise.