Divide-and-conquer Attack on LZ Chaotic Sequence Cipher Algorithm

This paper analyzes the security of a chaos-based stream cipher,it is found that the first several key stream bits of this chaotic cipher are not sensitive to the least significant bits of key,the parameter of chaotic mapping is not suitable as a key.Based on this information leaking,a divide-and-conquer attack is presented to decrease the entropy of key,and its effectiveness is confirmed by theoretic analysis and trials.