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Algebraic Attacks on Stream Ciphers with Linear Feedback
TLDR
This paper shows how to substantially lower the degree of these equations by multiplying them by well-chosen multivariate polynomials, and is able to break Toyocrypt in 2 CPU clocks, with only 20 Kbytes of keystream, the fastest attack proposed so far.
Cryptanalysis of Block Ciphers with Overdefined Systems of Equations
TLDR
A new criterion for design of S-boxes in block ciphers should not be describable by a system of polynomial equations that is too small or too overdefined, and this is suggested for both Serpent and Rijndael.
Efficient Algorithms for Solving Overdefined Systems of Multivariate Polynomial Equations
TLDR
It is provided strong evidence that relinearization and XL can solve randomly generated systems of polynomial equations in subexponential time when m exceeds n by a number that increases slowly with n.
How to Achieve a McEliece-Based Digital Signature Scheme
TLDR
This paper disproves the belief that code-based cryptosystems like McEliece do not allow practical digital signatures, and shows a way to build a practical signature scheme based on coding theory.
Fast Algebraic Attacks on Stream Ciphers with Linear Feedback
  • N. Courtois
  • Computer Science, Mathematics
    CRYPTO
  • 4 May 2003
TLDR
This paper shows how to substantially lower the degree of these equations by multiplying them by well-chosen multivariate polynomials, and is able to break Toyocrypt in 249 CPU clocks, with only 20 Kbytes of keystream, the fastest attack proposed so far.
Sosemanuk, a Fast Software-Oriented Stream Cipher
TLDR
The new synchronous software-oriented stream cipher Sosemanuk aims at improving SNOW 2.0 both from the security and from the efficiency points of view, and uses a faster IV-setup procedure, yielding better performance on several architectures.
Cryptanalysis of the TTM Cryptosystem
TLDR
This paper studies a more general family of TPM schemes: a triangular construction mixed with some u random polynomials and with some r of the beginning equations removed, and introduces a new attack for MinRank called 'Kernel Attack' that works for qr small.
On Subversive Miner Strategies and Block Withholding Attack in Bitcoin Digital Currency
TLDR
This paper revisits the concept of block withholding attacks and proposes a new concrete and practical block withholding attack which is shown to maximize the advantage gained by rogue miners.
QUARTZ, 128-Bit Long Digital Signatures
TLDR
This paper presents a first well defined algorithm and signature scheme, with concrete parameter choice, that gives 128-bit signatures while the best known attack to forge a signature is in 280.
Algebraic Cryptanalysis of the Data Encryption Standard
TLDR
It is demonstrated that in this paper, several interesting attacks on a real-life "industrial" block cipher can be found, and one of the attacks is the fastest known algebraic attack on 6 rounds of DES, which is quite interesting in itself.
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