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Cryptanalysis of Permutation–Diffusion-Based Lightweight Chaotic Image Encryption Scheme Using CPA

In order to meet the requirement of secure image communication in a resource-constrained network environment, a novel lightweight chaotic image encryption scheme based on permutation and diffusion has been proposed. It was claimed that this scheme can resist differential attacks, statistical attacks, etc. However, the original encryption scheme is found to be vulnerable and insecure to chosen-plaintext attack (CPA). In this paper, the original encryption scheme is analyzed comprehensively and attacked successfully. Only by choosing a full zero image as the chosen-plaintext of the diffusion phase, the encrypted image can be restored into permutation-only phase, and by applying the other chosen images as the chosen-plaintexts of the permutation phase, the map matrix which is equivalent to the secret key of the permutation phase can be further revealed. Experiments and analysis verify the feasibility of our proposed attack strategy.