Chosen-plaintext attack of an image encryption scheme based on modified permutation-diffusion structure
This work identifies a security vulnerability in a specific image encryption method, which is incremental as it critiques an existing scheme rather than proposing a new one.
The paper demonstrates that a recently proposed chaotic image encryption scheme (ICMPD) can be efficiently broken using a chosen-plaintext attack, with data complexity linear to the image size, and analyzes the relationship between its diffusion kernel and modulo addition/XOR operations.
Since the first appearance in Fridrich's design, the usage of permutation-diffusion structure for designing digital image cryptosystem has been receiving increasing research attention in the field of chaos-based cryptography. Recently, a novel chaotic Image Cipher using one round Modified Permutation-Diffusion pattern (ICMPD) was proposed. Unlike traditional permutation-diffusion structure, the permutation is operated on bit level instead of pixel level and the diffusion is operated on masked pixels, which are obtained by carrying out the classical affine cipher, instead of plain pixels in ICMPD. Following a \textit{divide-and-conquer strategy}, this paper reports that ICMPD can be compromised by a chosen-plaintext attack efficiently and the involved data complexity is linear to the size of the plain-image. Moreover, the relationship between the cryptographic kernel at the diffusion stage of ICMPD and modulo addition then XORing is explored thoroughly.