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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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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How Many 1024-bit Primes Have Backdoors?

So how did the NSA backdoored the Internet or did they??? New ground-breaking paper shows that DSA and DH mod P keys with 1024 bits are vulnerable to practical backdoors which can be exploited to break our secure communications. Few highlights: For such trapdoored primes the DL problem can be solved in 2 months by an academic cluster. The …

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Comparison of R&D Expenses in Different Countries

We have heard about the CIA/NSA Uber Apple/Google/Facebook, food industry, rampant imperialism which emanates from a handful of countries… and how these forces corrupt politicians and business circles in many other countries. Well actually in many cases it is self-inflicted misery. In many cases it is politicians and business people who run these countries do not …

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UCL Code Breaking Competition Winners Announced

On the V-Day and the 71st anniversary of defeating the Nazi Germany, we should remember how much the victory is owed to code breakers at Bletchley Park and elsewhere. 2016 UCL Code Breaking Competition (part of GA18). On this day it is my pleasure to announce the winners of the 2016 UCL Code Breaking competition. The winners …

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