Questions tagged [sha-2]
SHA-2 is a family of cryptographic hash functions designed by the NSA and published by NIST in 2001. The family includes various output lengths (224, 256, 384, and 512 bits).
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SHA256 collision resistance vs a CRQC?
In light of the assumed arrival of CRQC's NIST appears to no longer recommend SHA256 as a collision resistant hash.
I have been unable to find something definitive on the subject of how a 256-bit hash ...
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what are the security flaw of a simple Encryption algorithm made with SHA hash fonction? [duplicate]
I'm wondering what would be any major flaw of a simple Encryption algorithme based on Hash fonction like SHA:
The algorithm is:
Use SHA on a password and then keep hashing the output to concatenate a ...
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Do 512 bit hash functions meant for post quantum world? [duplicate]
for instance SHA2-512, İs it overkill to use currently?
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Why is SHA-2 considered an ARX construction when it also uses non-ARX operations?
SHA-2 makes use of non-ARX non-linear operators such as the Choice and Majority functions:
\begin{align}
\mathsf{Ch}(E,F,G) &= (E \wedge F) \oplus (\neg E \wedge G)\\
\mathsf{Ma}(A, B, C) &= (...
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Is the sha256 x86 extension close to optimal in silicon? (as it relates to a VDF)
I came across the Solana network utilizing sha256 as a "proof of history". They are using it as a pseudo-VDF (verifiable delay function). The reason it's pseudo is because verification is ...
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What is the correct value of SHA-512 message-length field if the message length is 3967 bits
In the steps of “Append the padding bits” in SHA-512 system, the message is padded so that its length is congruent to 896 mod 1024. I'm new to cryptography and I can't figure out the difference ...
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Who developed SHA-2 family?
When I look up who developed SHA-2 family, the result I get is along the lines of
SHA-2 was first published by the National Institute of Standards and
Technology (NIST) as a U.S. federal standard.
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How can a preimage attack on SHA-256 always succeed within 2^256 evaluations when done though brute force?
I was reading the Wikipedia page for SHA-256 (SHA-2) and came across the following statement:
For a hash function for which $L$ is the number of bits in the message digest, finding a message that ...
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SHA2 vs SHA3 popularity
Does anybody know or can point me to a source about SHA2 vs SHA3 usage statistics.
SHA3 is newer and is claimed to be more secure but ... is it more widely used in real life deployments?
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Is sha-256 better then sha-1 in aspects othen then the hash size?
Assume I create a hash using SHA-256 and then take only the first 160 bits of the hash, as the result. is the result more cryptographically secured than SHA-1? Or are the two algorithms equally secure ...
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NIST example shows extra hexadecimal characters in Block Contents of SHA512-256
I was recently trying to gain a better understanding of the SHA-512/256 algorithm and on this NIST example they use the word "abc" as the input. In the Block Contents, it shows the expected ...
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How did the developers of SHA-2 algorithm come to what we have now?
After a bit of research, I finally understand what's the step by step algorithm of SHA-2 (however, of course, I won't remember it myself).
But I don't understand what's the idea behind it. Did the ...
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Why does SHA2 work? [duplicate]
I was reading how bitcoin uses sha2
I understand how sha2 works procedurally (i.e. https://qvault.io/cryptography/how-sha-2-works-step-by-step-sha-256/), but I have no clue why it works.
Steps like s0 ...
rkoni
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SHA-256 doesn't follow a uniform distribution?
I have been playing with SHA-2-256 in Julia and I noticed that the hashes produced don't appear to follow a uniform distribution. My understanding of secure hashing algorithms is that they should ...
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Why is SHA3 more secure than SHA2?
Why are SHA3 algorithms considered more secure than their SHA2 counterparts? Surely in part, it is due to their resistance to length extension attacks. But specifically, when considering collision ...
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