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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A New Attack on Data Encryption Standard (DES)

There is abundant literature on the security of Data Encryption Standard (DES or 3DES). Today we have released a new way to attack this cipher, see Section 11 in here. Anyone who reads this paper should immediately see that the high confidence which have developed over decades in research community about our ability to design secure block …

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How to Backdoor a Block Cipher

I have written an elementary tutorial and a first proof of concept about how to backdoor a block cipher in a quite general setting. Potentially it applies to any block cipher. Success is not guaranteed though, see the paper. ADDED 2 JAN 2019: a new paper shows that invariants of higher degree are substantially more powerful. …

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XYZ and Saving an Extremely Rare Enigma Machine

Public donations are sought by Pilsudski Institute in London. The most prominent host of the institute is an extremely rare WW2 Enigma machine. This machine was made in France during WW2 to assist Polish code breakers in their daily code-breaking tasks [done in close collaboration with Bletchley Park, UK]. Only two such machines exist, see here …

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UCL InfoSec Visit at Bletchley Park – Friday 29 Sept 2017

Our trip took place 29 Sept 2017.  Some 32 UCL students participated. Students have explored the past in order to find role models for the future.           Due to large numbers, we have split into two groups for a guided Bletchley Park tour, and also had assisted at two bombe demonstrations. …

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Post-Quantum RSA

A very detailed study showing that RSA can be re-engineered in order to remain practical, yet it will no longer be broken by a quantum computer. The essence of the proposal is a multiple-prime RSA with great many 4096-bit primes and with 1 Terabyte public key. A significant potential weakness [for which however there is no …

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Silvio Micali – A Genius Which Will Stay in the Bottle

Silvio Micali, one of the most brilliant computer scientists on this planet has just re-invented democracy or blockchains or finance or law order and public authority and few other things, with his ALGORAND system. And some other brilliant crypto innovators are also doing the same thing: see DFINITY. Possibly this is what we really want, a …

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Interesting Parts in CIA Leaks

Schneier wrote: 8,761 classified CIA documents […] 2012-2016 […]it sounds like this cache of documents wasn’t taken from the CIA and given to WikiLeaks for publication, but has been passed around the community for a while — and incidentally some part of the cache was passed to WikiLeaks. […]  extraordinary collection […] several hundred million lines …

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