An Anomalous Differential Attack on a Block Cipher

In this attack a differential propagates with difficulty for some 20, 40 and up to 64 rounds. We can say that the propagation encounters some “friction”, because the non-linear functions do not always behave as the attacker would like them to behave. Everything looks normal and this is what happens for all block ciphers all …

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A Linear Annihilator Property and Strong Biases with Original DES S-boxes

In 2004 I have published a paper [Crypto 2004, Santa Barbara] in which I explain the concept of the so called Bi-Linear attack on DES. The old attack was not extremely strong. It is possible to see that two conditions would be necessary for such an attack to somewhat work well in cryptanalysis of DES: There …

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