A Self-synchronized Image Encryption Scheme

In this paper, a word based chaotic image encryption scheme for gray images is proposed, that can be used in both synchronous and self-synchronous modes. The encryption scheme operates in a finite field where we have also analyzed its performance according to numerical precision used in implementation. We show that the scheme not only passes a variety of security tests, but also it is verified that the proposed scheme operates faster than other existing schemes of the same type even when using lightweight short key sizes

A 3-Subset Meet-in-the-Middle Attack: Cryptanalysis of the Lightweight Block Cipher KTANTAN

status: publishe

Correlated Keystreams in Moustique

Abstract. Moustique is one of the sixteen finalists in the eSTREAM stream cipher project. Unlike the other finalists it is a self-synchronising cipher and therefore offers very different functional properties, compared to the other candidates. We present simple related-key phenomena in Moustique that lead to the generation of strongly correlated keystreams and to powerful key-recovery attacks. Our best key-recovery attack requires only 2 38 steps in the related-key scenario. Since the relevance of related-key properties is sometimes called into question, we also show how the described effects can help speed up exhaustive search (without related keys), thereby reducing the effective key length of Moustique from 96 bits to 90 bits