Cryptography Stack Exchange Community Digest

Top new questions this week:

What do you call a random number that affects the calculation, but not the result?

This is about the same random ladder algorithm as my previous question. It computes f(g,n,r)=n*g or g^n (depending on the group notation), where g is a generator of a group. Suppose n=5882353. This ...

terminology side-channel-attack  
user avatar asked by Pierre Abbat Score of 3
user avatar answered by Gilles 'SO- stop being evil' Score of 5

EC has lower CPU consumption than RSA under what condition?

When I searched Google, the top result said On average, processing for ECC is about four times less CPU-intensive than for RSA. Yeah, but under what condition? The page says "A 256-bit EC ...

elliptic-curves cpu  
user avatar asked by Damn Vegetables Score of 3
user avatar answered by fgrieu Score of 8

LCG seed prediction, from a set of values

The problem We are given a set of $n$ values in $V$. $V$ was made by shuffling (permuting) a sequence $S$ generated by an LCG $\text{G}(a,b,m,x_0)$ where $a$,$b$,$m$ and $x_0$ are all unknown. ...

encryption cryptanalysis lattice-crypto linear-cryptanalysis algebraic-attack  
user avatar asked by whyn0t Score of 2

Pseudorandom correlation generators for many small tensor products

Pseudorandom correlation generators (PCG) exist for tensor products, this is described in Figure 1 of [1]. Basically we want party 1 to hold $(x_0, z_0)$ and party 2 to hold $(x_1, z_1)$ such that $...

multiparty-computation pcg  
user avatar asked by lamba Score of 2
user avatar answered by Geoffroy Couteau Score of 1

The sum of independent discrete Gaussians is a discrete Gaussian

I am currently learning about lattice-based cryptography and, reading from A Decade of Lattice Cryptography by Peikert, specifically section 2.3, it emerges that [...] if the parameter s is greater or ...

lattice-crypto gaussian-noise  
user avatar asked by Jackmill Score of 2
user avatar answered by Mark Score of 1

How AES diffusion (permutation) does not impact ECB penguin pattern with in each block?

As per my understanding AES introduces diffusion in each block it encrypts even with ECB as mode of operation. If that is the case how the patterns are retained in each block? In this blog https://...

ecb  
user avatar asked by arjunballa Score of 1
user avatar answered by Paul Uszak Score of 0

CBC-MAC Forge Attack Question

I am trying to understand how the forgery attack works when using the CBC-MAC Algorithm If I have an authenticated plaintext message and a mac tag ($p_0$, $t_0$) and another authenticated plaintext ...

mac cbc cbc-mac forgery  
user avatar asked by CryptoGuru Score of 1
user avatar answered by kelalaka Score of 0

Greatest hits from previous weeks:

How are the AES S-Boxes calculated?

I'm trying to understand how the AES S-Boxes are calculated. I understand how the multiplicative inverse is calculated over $GF(2^8)$, but I'm confused by the description of the affine transformation. ...

aes s-boxes  
user avatar asked by ConditionRacer Score of 17
user avatar answered by Richie Frame Score of 17

Why hash the message before signing it with RSA?

The diagram below illustrates the process of digitally signing a message with RSA: As diagram shows, the message is first hashed, and the signature is then computed on the hash, rather than on the ...

hash rsa signature protocol-analysis forgery  
user avatar asked by evening Score of 56
user avatar answered by DrLecter Score of 37

How do ciphers change plaintext into numeric digits for computing?

For example, in RSA, we use this for encryption: $ciphertext = (m^e \mod n)$ and for decryption. If our message is "hello world", then what number do we have to ...

rsa  
user avatar asked by Ted Score of 20
user avatar answered by marstato Score of 15

Avalanche effect in DES

I couldn't understand the avalanche effect in DES. Could someone explain how avalanche effect happens in DES

encryption block-cipher des feistel-network  
user avatar asked by user5507 Score of 9
user avatar answered by woliveirajr Score of 15

Chinese Remainder Theorem and RSA

Wikipedia has a nice section regarding the speedup of the RSA decryption using the Chinese Remainder Theorem here. I need to understand the implementation of a similar speedup for the encryption ...

rsa homomorphic-encryption  
user avatar asked by Mihai Todor Score of 16
user avatar answered by poncho Score of 27

How does asymmetric encryption work?

I've always been interested in encryption but I have never found a good explanation (beginners explanation) of how encryption with public key and decryption with private key works. How does it ...

public-key  
user avatar asked by Senad MeŇ°kin Score of 57
user avatar answered by Thomas Pornin Score of 42

In RSA, why is it important to choose e so that it is coprime to φ(n)?

When choosing the public exponent e, it is stressed that $e$ must be coprime to $\phi(n)$, i.e. $\gcd(\phi(n), e) = 1$. I know that a common choice is to have $e = 3$ (which requires a good padding ...

rsa modular-arithmetic  
user avatar asked by Martin Score of 31
user avatar answered by poncho Score of 35

Can you answer these questions?

Which is the fundamental difference between a signature of a message and a zero-knowledge argument of a signature for that message?

Say that I have a signing/verification key pair $(sk,vk)$ and I generate a signature $\sigma$ over a message $m$. Then, I want to prove to someone else of this fact, which can be done in two different ...

signature zero-knowledge-proofs  
user avatar asked by Bean Guy Score of 1

Post Quantum Cryptography - Verifying if there are no backdoors in these selected algorithms: crystals-kyber, crystals-dilithium, falcon, sphincs+

I was looking through https://csrc.nist.gov/projects/post-quantum-cryptography/selected-algorithms-2022 How can one begin to mathematically verify if there are no backdoors to these selected post ...

post-quantum-cryptography backdoors  
user avatar asked by Nathan Aw Score of 1

How do I try a timing attack on a public-key implementation on a general-purpose computer?

I'm writing a higher-order function in Haskell for use in public-key algorithms; it works equally well for RSA or elliptic curves. I'd like to test it for susceptibility to side channel attacks. How ...

public-key elliptic-curves side-channel-attack  
user avatar asked by Pierre Abbat Score of 1
user avatar answered by fgrieu Score of 0
You're receiving this message because you subscribed to the Cryptography community digest.
Unsubscribe from this community digest       Edit email settings       Leave feedback       Privacy
Stack Overflow

Stack Overflow, 110 William Street, 28th floor, New York, NY 10038

<3