On the security defects of an image encryption scheme

• Main Authors: C., Li, S., Li, M., Asim, J., Nunez, G., Alvarez, G., Chen
• Format: Article
• Published: 2009
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utp.edu.my/457/1/paper.pdf; http://www.scopus.com/inward/record.url?eid=2-s2.0-67349203285&partnerID=40&md5=5385f9470ba91a7ead6bdefd47b999d7; http://eprints.utp.edu.my/457/
• Institution: Universiti Teknologi Petronas

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 K₁₀ 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: fenced(K_i mod 128)_{i = 4}¹⁰, which works very well when K₁₀ is not too large; (4) when K₁₀ 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. © 2009 Elsevier B.V. All rights reserved.