SECURE SPATIOTEMPORAL CHAOTIC IMAGE/VIDEO CRYPTOSYSTEM

摘要

Recently, Rhouma and Belghith [12] stated that chaotic cryptosystem for image and video is vulnerable to a chosen ciphertext/plaintext attack, and then proposed an improved version by utilizing PCBC mode. This paper demonstrates that neither of the schemes can sustain known plaintext attacks. An adversary can obtain the key stream as an equivalent key by only one known plaintext. In addition, a fix to the problem is proposed.