Correlation Power Analysis in PicoCTF 2023
Table of Contents Introduction Solving the Challenge Additional Thoughts Conclusion Introduction The hardest and also most interesting cryptography challenge of PicoCTF 2023 involved undoing AES using a side channel attack, specifically power analysis. If I’m going to be honest, it was a pretty big surprise to see a side channel attack be the primary challenge within Pico but it was definitely a fun experience. Solving the Challenge The core idea of correlation power analysis (CPA) is to take the non-linear part of AES, the S-box lookup and use that bit of info to extract more information about the key....