Paper 2007/397

On the security defects of an image encryption scheme

Chengqing Li, Shujun Li, Muhammad Asim, Juana Nunez, Gonzalo Alvarez, and Guanrong Chen


This paper studies the security of a recently-proposed chaos-based image encryption scheme, and points out the following problems: 1) there exist a number of invalid keys and weak keys, and some keys are partially equivalent for encryption/decryption; 2) given one chosen plain-image, a subkey $K_{10}$ can be guessed with a smaller computational complexity than that of the simple brute-force attack; 3) given at most 128 chosen plain-images, a chosen-plaintext attack can possibly break the following part of the secret key: $\{K_i\bmod 128\}_{i=4}^{10}$, which works very well when $K_{10}$ is not too large; 4) when $K_{10}$ is relatively small, a known-plaintext attack can be carried out with only one known plain-image to recover some visual information of any other plain-images encrypted by the same key.

Available format(s)
Secret-key cryptography
Publication info
Published elsewhere. Unknown where it was published
Contact author(s)
swiftsheep @ hotmail com
2007-10-14: received
Short URL
Creative Commons Attribution


      author = {Chengqing Li and Shujun Li and Muhammad Asim and Juana Nunez and Gonzalo Alvarez and Guanrong Chen},
      title = {On the security defects of an image encryption scheme},
      howpublished = {Cryptology ePrint Archive, Paper 2007/397},
      year = {2007},
      note = {\url{}},
      url = {}
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