Crypto-analysis of the Encryption Algorithm Rijndael

A special property of the S-box of the block cipher Rijndael is found, which states that for any x1, x2， and Δ∈SBYTE，if S(x1)S(x1Δ)=S(x2)S(x2Δ)，then either x1=x2，or x1=x2Δ, where SBYTE denotes the set of all bytes. This property is helpful for mounting an efficient attack on Rijndael, that is illustrated by a simple example in this paper.