Cryptanalysis of multiple chaotic systems based public key encryption technique

Abstract

A novel public key encryption technique based on multiple chaotic systems has been proposed. This scheme employs m-chaotic systems and a set of linear functions for key exchange over an insecure channel. The security of the proposed algorithm grows as (NP)m, where N, P are the size of the key and the computational complexity of the linear functions, respectively. In this paper, the fundamental weakness of the cryptosystem is pointed out and a successful attack is described. Given the fact that any complex linear transformations on a vector will make the norm of the vector approximate linear growth, we present an attack that permits recovering the corresponding secret key from the public key and the initial value. Both theoretical and experimental results show that the attacker can access the secret key without any difficulty. The lack of security discourages the use of such algorithm for practical applications.