How Resistant are Sboxes to Power Analysis Attacks?

Side channel analysis and, in particular, differential power analysis (DPA) has become a prominent technique to attack cryptographic devices. This technique can be used to reveal the secret key stored in security devices by monitoring the power consumption of certain cryptographic algorithm operations and applying statistical processing. In this paper, an evaluation of power analysis attacks of the SBox component in four different ISO/IEC18033-3 encryption algorithms, namely AES, DES, SEED and CAST-128, is presented. Based on this recommendations for the design of DPA-resistant SBoxes are proposed. To the best of the authors´ knowledge this paper also presents the first practical DPA attack against an ASIC hardware implementation of the SEED encryption algorithm (without using chosen plaintext).