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Top Questions

15 votes
6 answers
6k views

Why do web-services tend to use preshared secret keys for client authentication instead of public keys?

2 votes
3 answers
1k views

Is there a security risk to use AES-CBC as stream cipher?

8 votes
2 answers
1k views

Validating an RSA public key

1 vote
1 answer
2k views

Should we really rely on "Cryptographically Secure Pseudo-Random Number Generators" (CSPRNG) alone to guarantee secure random output?

5 votes
3 answers
464 views

When working in a subgroup of EC in EdDSA (especially Ed255190), how is it OK to use operations different from that of the main group?

8 votes
1 answer
533 views

Does "SHA-256/192" use different initial values from SHA-256?

4 votes
3 answers
160 views

Why is AES better than one-time pad?

2 votes
1 answer
230 views

Find Ed25519 Y Coordinate from X Coordinate

3 votes
1 answer
374 views

What asymmetric encryption to use that is safe against quantum computers?

1 vote
3 answers
78 views

Are the structures (groups/rings) that RSA operations are performed on actually R-modules?

2 votes
2 answers
117 views

Examples of systems using partially homomorphic schemes

4 votes
2 answers
132 views

How to attest simultaneous knowledge of $2$ private keys?

1 vote
3 answers
157 views

Base64 or hex to attach auth tokens to URL?

1 vote
1 answer
145 views

Solving system of equation based on RSA

3 votes
2 answers
111 views

Ed25519 - Is there a reason to not trust the signer - i.e. can there be a dishonest signer?

0 votes
1 answer
84 views

Post quantum hybrid model and its security

4 votes
1 answer
166 views

Why such a complicated way of cofactor clearing?

4 votes
1 answer
162 views

How are the unified addition formulae in extended twisted Edwards coordinates derived from the affine addition formulae?

0 votes
1 answer
178 views

Is there some restrictions on values of p,q,d,e etc in RSA algorithm while trying to encrypt English Ciphertext?

2 votes
0 answers
278 views

In RSA, are e and d technically equivalent? [duplicate]

4 votes
1 answer
164 views

Is it true that Public keys with even y coordinate correspond to private key that are less than n/2 and vice versa? (Secp256k1)

1 vote
2 answers
58 views

Debug bcrypt iterations with a static salt [closed]

4 votes
2 answers
84 views

Randomized encodings and Indistinguishability obfuscation

0 votes
2 answers
65 views

Learning RSA: decryption yields inconsistent result after modular arithmetic

1 vote
1 answer
107 views

Bactracking resistance PRNG - real world usage

0 votes
2 answers
111 views

SHA256 - alternative algorithm to receive same hash?

2 votes
2 answers
84 views

How is the edwards448 generator derived from the curve448 generator in RFC 7748?

1 vote
1 answer
84 views

Encryption and decryption for LWE

0 votes
1 answer
65 views

Merkle–Damgård construction - the bigger input, the longer time to compute hash?

2 votes
1 answer
102 views

How easy is it to know how many preimages an image might have, given that there's at least one (preimage, image) pair?

2 votes
1 answer
97 views

In Ed25519, why not make both batch & unbatched verification follow the cofactored verification approach rather than unbatched using cofactorless?

0 votes
2 answers
95 views

How is AES256-GCM auth tag used in decryption

1 vote
1 answer
121 views

Is it possible to design an algorithm that is based on the xor of the plaintext bits?

2 votes
1 answer
72 views

Statistical Distance and Learning with Rounding

2 votes
1 answer
54 views

Interactive Proofs: Why $\delta \lt \frac 13$ for Soundness & Completeness?

-2 votes
2 answers
89 views

How to modify elliptic curve point?

2 votes
1 answer
87 views

Create a control hash string from different sources, is there a difference, advantage or disadvantage in comparison when using this ways?

2 votes
1 answer
67 views

How does this libgcrypt elgamal decryption work?

2 votes
1 answer
106 views
+50

The significance of rewinding a simulation in an ZK interactive proof

0 votes
1 answer
61 views

Is MAC unnecessary for client side encryption?

1 vote
1 answer
61 views

Symmetric MAC benefit

2 votes
1 answer
70 views

what is IV predictable?

2 votes
1 answer
67 views

Clarification on expected number of plaintext, ciphertext pairs needed to identify AES keys

1 vote
1 answer
86 views

"Near" Pseudorandom Function

1 vote
1 answer
66 views

(In)security of multiplicative blinding / one-time-pad in a commutative ring

1 vote
1 answer
83 views

HKDF-Expand max output length

0 votes
1 answer
49 views

Is it insecure to make HMAC SHA1 message and corresponding hash public?

1 vote
0 answers
102 views

Does this function yields to a PRF?


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