Security Analysis of the Full-Round CHESS-64 Cipher Suitable for Pervasive Computing Environments

Wireless networks, telecommunications, and information technologies connected devices in pervasive computing environments require a high speed encryption for providing a high security and a privacy. The CHESS-64 based on various controlled operations is designed for such applications. In this paper, however, we show that CHESS-64 doesn’t have a high security level, more precisely, we present two related-key differential attacks on CHESS-64. The first attack requires about 244 data and 244 time complexities (recovering 20 bits of the master key) while the second attack needs about 239 data and 239 time complexities (recovering 6 bits of the master key). These works are the first known cryptanalytic results on CHESS-64 so far.