2024 年 32 巻 p. 352-357
The symmetric-key block cipher SLIM, which was proposed by Aboushosha et al., is a lightweight cryptographic algorithm. Designed for radio frequency identification (RFID) systems, SLIM is a 32-bit block cipher based on the Feistel structure with an 80-bit secret key. We present a higher-order differential attack on reduced-round SLIM. We discovered some 9-round higher-order differential characteristics from computer experimentation. We show that 12-round SLIM is attackable with 231 data and 277.1 times of encryption using the 31st-order differential characteristic. Because the recommended number of rounds is 32, SLIM is demonstrated as secure against higher-order differential attack.