Related-Key Amplified Boomerang Attack on Full-Round MM-128

Recently, the use of open platforms with various network functions and hardware interfaces has been increasing in various fields such as the Internet of Things, smart buildings, and industrial automation. In this new device environment, data-dependent operation (DDO) usage-based cryptographic design based on the control element have been introduced, which is suitable for ensuring high-efficiency performance and network security of the CIA (confidentiality, integrity, accessibility) security model. Among them, the MM-128 proposed by Hieu and his colleagues is a high-speed block cipher that uses the latest FPGA devices to increase the hardware implementation efficiency of block ciphers. It is composed of 9 rounds and uses a 256-bit key. However, most data-dependent permutation (DDP), DDO, and switchable data-dependent operation (SDDOS)-based block ciphers are vulnerable to related-key attacks owing to their simple key scheduling processes, including this paper’s target algorithm MM-128. This paper presents a related-key amplified boomerang attack that is more efficient than an exhaustive attack as the first known result. The attack on MM-128 requires 272.5 related-key chosen plaintexts and 2132.5 encryptions. In future research, this work is expected to be extended and improved with the latest boomerang connectivity table (BCT) and differential-linear connectivity table (DLCT) techniques to obtain better cryptanalytic results.