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16

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5

answers

3k

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Is a PRG more costly than AES or any other encryption standard?

encryption keys one-time-pad

modified Oct 17 at 15:35 α CVn 193

19

votes

1

answer

3k

views

Why is SHA-3 robust against Length-Extension Attacks?

mac sha-3

modified Sep 26 at 7:21 Vipul Srivastava 1

15

votes

2

answers

5k

views

Calculating entropy within xkcd 936: Password Strength

passwords entropy

answered Sep 25 at 10:45 Paul Uszak 6,266

8

votes

5

answers

2k

views

Hash to prime numbers?

hash accumulators

answered Oct 13 at 16:26 Vadym Fedyukovych 1,397

6

votes

3

answers

2k

views

Finding flaw in cryptographic protocol

protocol-analysis standards

modified Oct 5 at 0:50 Paul Uszak 6,266

3

votes

1

answer

681

views

RSA decryption with small exponent - no “public keys”

rsa

modified Oct 12 at 19:24 Ella Rose 14k

3

votes

4

answers

2k

views

How safe is a book cipher? How would you break it?

encryption

answered Oct 2 at 14:32 Emil Jeřábek 121

5

votes

2

answers

775

views

Consuming of entropy

entropy

modified Sep 28 at 14:44 Swashbuckler 360

7

votes

2

answers

697

views

How fast does a pseudorandom number generator have to be in order to be competitive?

pseudo-random-generator

modified Sep 29 at 13:27 Community♦ 1

6

votes

1

answer

595

views

What does “seed” mean in cryptography?

pseudo-random-generator terminology

modified 22 hours ago Ilmari Karonen 32.8k

7

votes

2

answers

616

views

Why do some key derivation functions (like PBKDF2) use a salt?

key-derivation salt

modified Oct 2 at 15:14 fgrieu 74.4k

3

votes

3

answers

338

views

What is different below two Ciphersuites?

encryption hash tls openssl

modified Oct 6 at 16:09 polfosol 127

1

vote

3

answers

242

views

Password re-use by another person or on another service

passwords salt

modified yesterday Saptarshi Basu 208

4

votes

3

answers

210

views

Is it possible to exactly reverse engineer an unknown cipher inside a black box?

cryptanalysis algorithm-design security-definition

modified Oct 17 at 10:31 fgrieu 74.4k

2

votes

2

answers

332

views

Is there a symmetric cipher that is explicitly designed to be slow?

symmetric reference-request

modified 2 days ago kelalaka 1,346

2

votes

1

answer

229

views

Is every block padded with AES?

padding-oracle

answered Sep 29 at 20:29 poncho 87k

5

votes

2

answers

79

views

Motivation of Adversarial Indistinguishability Experiment

provable-security chosen-plaintext-attack

answered Oct 8 at 9:22 Yehuda Lindell 17k

2

votes

2

answers

414

views

Optimal bit-change-probability of the avalanche effect for hashes

hash avalanche

modified Oct 7 at 10:16 fgrieu 74.4k

2

votes

1

answer

117

views

Is DES secure under CBC?

cbc des

modified Oct 2 at 9:08 kelalaka 1,346

3

votes

2

answers

136

views

Are Hash Palindromes Possible?

hash

modified Sep 26 at 21:41 Korosensei 56

7

votes

2

answers

117

views

Regular and Efficient doubling in $GF(2^n)$

implementation modular-arithmetic

modified yesterday fgrieu 74.4k

3

votes

1

answer

187

views

Why can't decrypt with OpenSSL if salt changed (for CBC and ECB)

cbc openssl salt aes256

modified Sep 30 at 20:50 e-sushi♦ 13.3k

3

votes

1

answer

166

views

Is SHA1 secured enough as a PRNG

random-number-generator sha-256 sha-1 semantic-security

answered Oct 17 at 16:23 Maarten Bodewes 49.9k

3

votes

1

answer

203

views

Attack of the Middle Square Weyl Sequence PRNG

cryptanalysis pseudo-random-generator

modified Sep 30 at 10:50 fgrieu 74.4k

1

vote

1

answer

141

views

How can DNA Computing solve very complex problems that can present in cryptography?

dna-cryptanalysis

modified Oct 17 at 13:04 SEJPM♦ 27.3k

0

votes

1

answer

85

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Why 3 round Feistel cipher are not common

block-cipher feistel-network luby-rackoff

answered Oct 13 at 17:08 CodesInChaos♦ 20.4k

2

votes

1

answer

162

views

If the Riemann hypothesis solved

public-key riemann

answered Sep 28 at 15:01 SAI Peregrinus 1,870

0

votes

1

answer

76

views

Which block cipher mode to use?

block-cipher cbc modes-of-operation ecb

modified Sep 27 at 15:16 Maarten Bodewes 49.9k

5

votes

1

answer

71

views

How is ZKPP better than signing nonces?

authentication zero-knowledge-proofs

modified Sep 25 at 17:55 Maeher 2,823

3

votes

1

answer

91

views

What does Keccak being “efficiently invertible” mean?

hash collision-resistance sha-3 keccak quantum-resistance

modified Oct 6 at 10:01 e-sushi♦ 13.3k

2

votes

2

answers

174

views

What is the name of an attack where the compromise of one key compromises the whole system?

encryption cryptanalysis provable-security attack

modified 1 hour ago fgrieu 74.4k

1

vote

1

answer

140

views

Vulnerabilities of AES method that uses MD5 to create the key

aes md5

modified Oct 3 at 2:01 Maarten Bodewes 49.9k

1

vote

3

answers

108

views

Could ANY cipher serve as the foundation for a public key cryptosystem?

public-key symmetric trapdoor

modified Oct 8 at 22:23 Maarten Bodewes 49.9k

3

votes

1

answer

63

views

Practical quantum attacks on AES - Is AES-128 used in a block mode vulnerable to attack using quantum algorithms

aes post-quantum-cryptography quantum-cryptography

modified 18 hours ago Maarten Bodewes 49.9k

2

votes

2

answers

133

views

Attacking AES128 with Grover's algorithm

aes post-quantum-cryptography quantum-cryptography quantum-resistance

modified Oct 14 at 15:32 Maarten Bodewes 49.9k

0

votes

2

answers

100

views

Why does the key for a one-time pad have to be uniformly distributed? [closed]

one-time-pad perfect-secrecy

answered Oct 8 at 4:05 Thomas M. DuBuisson 1,683

1

vote

1

answer

97

views

With DES, is ECB encryption mode equivalent to CBC with null IV for short data blocks?

cbc des ecb

modified Oct 15 at 19:03 kelalaka 1,346

0

votes

3

answers

119

views

Hide secrets in an article composed with Machine Learning?

steganography

modified Oct 9 at 15:02 Ginswich 181

2

votes

1

answer

71

views

GUIDs as a salt

salt password-hashing

modified Oct 17 at 2:45 rmalayter 1,565

4

votes

1

answer

70

views

Do I understand HMAC-SHA-xxx and HMAC-SHA-xxx-yyy correctly?

hmac

modified 2 days ago Maarten Bodewes 49.9k

0

votes

2

answers

54

views

Do I need to know the curve for ECIES decryption?

encryption elliptic-curves ecies

modified Sep 25 at 15:05 Maarten Bodewes 49.9k

0

votes

2

answers

65

views

Inverse MixColumns Operation of AES

aes aes-gcm

answered Sep 25 at 18:05 kelalaka 1,346

7

votes

1

answer

176

views

Why is Approximate GCD a hard problem?

homomorphic-encryption lattice-crypto number-theory

answered Oct 12 at 16:35 robertkin 126

1

vote

2

answers

171

views

How secure is ChaCha20? [closed]

encryption cryptanalysis stream-cipher chacha

modified Oct 1 at 20:36 Ella Rose 14k

1

vote

2

answers

80

views

AES blocks with a counter

aes mac modes-of-operation

modified Oct 13 at 20:55 kelalaka 1,346

2

votes

1

answer

62

views

Could one make an asymmetric encryption scheme based on Sudoku?

public-key

answered Sep 24 at 6:11 kodlu 7,914

1

vote

1

answer

102

views

How does one construct a 27x27 tabula recta for 2-of-3 secret sharing?

modified Oct 8 at 21:11 fgrieu 74.4k

4

votes

1

answer

130

views

Is there a group where CDH is easy but DLog is hard?

discrete-logarithm hardness-assumptions

answered Oct 7 at 20:20 Mikero 4,951

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