1. Introduction XTS-AES (XEX-based Tweaked-codebook mode with ciphertext Stealing using AES) is a block cipher mode of operation specifically designed for encrypting data on storage devices. Its most common instantiation, XTS-AES-128 , uses the Advanced Encryption Standard with a 128-bit key size. Unlike streaming modes (e.g., CTR, GCM) or other block modes (e.g., CBC), XTS is tailored to address the unique threats and performance requirements of sector-based storage (hard drives, SSDs, USB flash drives).