On the security of a new image encryption scheme based on a chaotic function

Abstract

This paper analyses the security of a recently proposed image encryption algorithm and shows a series of weaknesses that make it unusable in applications requiring medium or high levels of security. We show that the algorithm has some minor flaws, such as impractical decryption or impossibility to encrypt black images as well as a major flow, linearity, which makes it vulnerable to cryptanalysis. We present a chosen cipher text attack and show that, after the cryptanalysis, an attacker can successfully decrypt any cipher image, without knowledge of the secret key.