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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ZeroCash was broken, and nobody have noticed

A bug which allows unlimited creation of coins was found and fixed in ZeroCash. It is a sophisticated and subtle security flaw. We read that: To exploit the counterfeiting vulnerability, an attacker would have needed to possess information found in the large MPC protocol transcript that was made available shortly after the launch of Zcash. …

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Happy Birthday Bitcoin, 10 Years!

On January 3rd we celebrate 10 years since bitcoin network started operation. Long live all crypto currencies, especially those which actually are real innovators, and bring new technology such as advanced crypto techniques to the market. Let a thousand crypto flowers bloom. P.S. It is also 20 years and 2 days after the introduction of …

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The Low Cost of 51% Attacks

A web page shows that many crypto currencies lack protection against 51% attacks. For example to double spend in Dash, one needs to pay only 14K$ per hour. To double spend in bitcoin private, 1000$ will suffice. And course benefits of double spending can easily outweigh the costs. In addition some of the higher numbers are questionable. There …

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My Position on UCL Strike

A large number of UCL academics have yesterday started a large scale strike lasting for many weeks. These people are sacrificing their salary [UCL will cut their pay down] and there is a strong support for the strike. The strike is organised on the premises that our employer, UCL, are? cutting down their pension contributions or ending guaranteed income schemes …

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