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Top Questions

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12

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3

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What password hash function for the next 50 years?

hash password-hashing

modified Jul 25 at 16:40 Azxdreuwa 235

10

votes

2

answers

1k

views

What is the minimum and maximum value of an RSA private exponent?

rsa key-size

modified Aug 10 at 3:14 Maarten Bodewes 46.6k

15

votes

1

answer

2k

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Why would anyone choose 3DES over AES in software?

aes 3des

modified Aug 11 at 14:56 Peter Mortensen 109

3

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3

answers

2k

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Can multiplication of two primes be seen as a strong cipher?

homomorphic-encryption one-time-pad prime-numbers factoring commutative-encryption

modified Jul 30 at 10:30 Community♦ 1

7

votes

1

answer

959

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Why does BCRYPT_RNG_DUAL_EC_ALGORITHM get removed from CNG API on Windows 10?

random-number-generator nsa dual-ec-drbg

modified Jul 23 at 14:57 SEJPM♦ 25.6k

6

votes

1

answer

2k

views

How can I securely encrypt the same message multiple times?

rsa

modified Jul 31 at 15:32 Maarten Bodewes 46.6k

5

votes

2

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871

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Why do algebraic proofs apply to cryptography?

implementation number-theory group-theory

modified Jul 19 at 11:20 fgrieu 71k

8

votes

2

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375

views

Which attacks are prevented by the different initial hash values for SHA-2 with truncated output?

algorithm-design sha-256 initialization-vector sha-2 sha-512

modified Aug 7 at 1:09 Maarten Bodewes 46.6k

3

votes

3

answers

493

views

When do I need to use CBC and HMAC?

aes hmac cbc cbc-mac

modified 2 days ago fgrieu 71k

10

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2

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348

views

Is this definition of an RSA modulus safe?

rsa

answered Aug 2 at 19:20 Hyperflame 345

5

votes

2

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143

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Security difference between $\mathrm{Keccak}(k\mathbin\|x)$ and $\mathrm{Keccak}(x\mathbin\|k)$

hash hmac keccak

modified Aug 2 at 4:03 lyrically wicked 404

3

votes

2

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228

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Speck with signed math

speck

modified Jul 20 at 17:59 fgrieu 71k

1

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5

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197

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What is the mathematical property stating that it is hard to find a collision in the AES algorithm?

aes collision-resistance

answered Jul 27 at 7:55 Yehuda Lindell 16.5k

2

votes

3

answers

185

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Why is it impossible to find the private key from the public key?

encryption public-key cryptocurrency

modified Jul 30 at 0:21 Rodrigo de Azevedo 135

1

vote

1

answer

198

views

How can I implement ID based encryption using RSA?

rsa identity-based-encryption

modified Jul 26 at 17:34 Geoffroy Couteau 7,202

2

votes

1

answer

305

views

Twofish fails Dieharder test

twofish

modified 1 hour ago fgrieu 71k

3

votes

2

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100

views

Could a 6502 CPU safely compute a SHA-1 hash in a reasonable length of time?

hmac two-factor-authentication

modified 16 hours ago fgrieu 71k

2

votes

2

answers

215

views

Security of AES ECB for 128 bit random data

aes ecb

modified Jul 24 at 5:19 Daffy 1,477

8

votes

1

answer

156

views

Can the lengths of HTTPS requests be used to deduce which public pages on a site are visited?

tls side-channel-attack

answered Aug 5 at 14:05 Mikero 4,319

1

vote

3

answers

121

views

Is there a consensus on what text encoding to use when hashing a string?

hash implementation encoding

modified Jul 22 at 16:06 e-sushi♦ 13.2k

5

votes

1

answer

137

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How can homomorphic encryption be probabilistic while allowing for math to be conducted?

homomorphic-encryption random-oracle-model

modified Jul 27 at 5:49 fgrieu 71k

4

votes

2

answers

104

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Atomic multi-party commitments

signature dsa multiparty-computation

modified Aug 9 at 6:55 Lucian Boca 192

4

votes

3

answers

102

views

How to Calculate GE of Sbox?

block-cipher implementation

modified Aug 3 at 10:13 asante 51

2

votes

2

answers

202

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Mutating a SHA-2 input would allow us to have multiple hashes for a single input, would this increase SHA-2's security?

sha-2

modified Aug 5 at 17:17 Maarten Bodewes 46.6k

5

votes

2

answers

66

views

when does the first rotor in Enigma machine rotate?

enigma

answered Aug 9 at 21:00 lpaseen 161

2

votes

2

answers

84

views

What do people mean when they talk about forward secrecy in ciphers?

encryption forward-secrecy

modified Jul 22 at 14:18 SEJPM♦ 25.6k

4

votes

1

answer

132

views

Identifying the type of algorithm for a PRNG that uses modular multiplication and addition

random-number-generator pseudo-random-generator

modified Aug 11 at 1:41 Paŭlo Ebermann 18.2k

2

votes

1

answer

126

views

AES with linear S-Box

aes s-boxes affine-cipher

answered Aug 10 at 14:54 poncho 84.6k

1

vote

2

answers

264

views

Is it safe to use a timestamp to build a nonce?

encryption gcm nonce chacha

modified Aug 7 at 19:05 Luis Casillas 8,897

5

votes

2

answers

55

views

Can RFC 5649 be used to wrap multiple keys with the same KEK?

collision-resistance key-wrap

modified Aug 9 at 20:07 fgrieu 71k

1

vote

2

answers

126

views

ECIES need for KDF

ecies

answered Jul 18 at 20:50 Erik Aronesty 160

2

votes

2

answers

72

views

Does AES use different keys for each block of plaintext?

encryption keys

modified Aug 1 at 9:45 Maarten Bodewes 46.6k

4

votes

2

answers

77

views

uuidgen has consistent 13th digit and it's 4

randomness

modified Aug 7 at 12:08 Paul Uszak 5,389

5

votes

2

answers

76

views

Socialist Millionaires variant, where only one party learns $x=y$?

zero-knowledge-proofs private-set-intersection

modified Jul 19 at 3:50 Mikero 4,319

1

vote

2

answers

91

views

In RSA, is it possible to compute the private key if one knows one of the primes used to generate n?

rsa key-derivation prime-numbers

modified Aug 6 at 10:54 fgrieu 71k

2

votes

2

answers

113

views

AES and ECDH key

encryption aes diffie-hellman

modified Aug 1 at 22:47 Maarten Bodewes 46.6k

4

votes

1

answer

87

views

Synthetic Jitter to Combat Timing Attacks

randomness

modified Aug 12 at 22:07 Lery 3,087

0

votes

5

answers

142

views

Pseudorandom number generator for which it is impossible to deduce the seed

random-number-generator pseudo-random-generator

modified Aug 9 at 13:17 Maarten Bodewes 46.6k

2

votes

1

answer

86

views

Right way to hash elliptic curve points into finite field

hash elliptic-curves implementation

modified Jul 20 at 4:27 jadb 136

2

votes

1

answer

86

views

How to solve this ECDLP?

elliptic-curves discrete-logarithm

modified Aug 11 at 0:55 byks 20

1

vote

1

answer

73

views

Hashing based on the discrete logarithm problem

hash elliptic-curves collision-resistance preimage-resistance 2nd-preimage-resistance

modified 2 days ago Yehuda Lindell 16.5k

1

vote

2

answers

115

views

Append text to file without decrypting & encrypting again

encryption public-key

answered 22 hours ago Jakub N 21

3

votes

1

answer

112

views

What form of ECC can we use to make sure our newly invented ECC based crypto-systems are quantum secure?

elliptic-curves post-quantum-cryptography

modified yesterday Aleksander Rassasse 168

3

votes

2

answers

108

views

Is this a good way extracting randomness from some physical process?

random-number-generator

answered Jul 31 at 11:09 Paul Uszak 5,389

1

vote

2

answers

105

views

How do I check if the output of my CFB TEA encryption algorithm is correct?

encryption cfb tea

answered Jul 24 at 0:19 Luis Casillas 8,897

2

votes

1

answer

63

views

Questions about the Curve25519-donna implementation

elliptic-curves finite-field montgomery-multiplication prime-field

modified Aug 10 at 13:58 Vega4 74

7

votes

1

answer

97

views

Is Bouncycastle RSA+OAEP implementation vulnerable to Manger’s attack?

encryption rsa chosen-ciphertext-attack oaep

answered Jul 29 at 2:48 dave_thompson_085 3,041

3

votes

1

answer

115

views

How to find a primitive cube root of unity

elliptic-curves pairings

modified Jul 28 at 1:34 fkraiem 6,088

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