Cryptanalysis of a novel image fusion encryption algorithm based on DNA sequence operation and hyper-chaotic system

We studied the security features of a recently proposed image encryption scheme [Zhang et al., Optik 124(18) (2013) 3596] based on DNA sequence operation and hyper-chaotic system. We showed that all kinds of DNA encoding and decoding schemes used in this encryption scheme are equivalent to each other, which makes it a confusion-only encryption scheme. This paper successfully broke the scheme with the chosen plaintext attack method.