Linked Questions

79 votes
1 answer
48k views

How easy is it in 2022 to find a SHA1 collision?

Most of the answers I can find date to years back where the first collision(s) were found, but hardware mainly GPUs have progressed a lot in the past few years (with for example the new line of 3090s ...
Hormoz's user avatar
  • 799
37 votes
3 answers
8k views

Does "Shattered" actually show SHA-1-signed certificates are "unsafe"?

Note: I am not advocating anyone continues using SHA1-signed certificates: they are dead as far as security is concerned and should no longer be used. I'm just trying to clarify my understanding of ...
TripeHound's user avatar
16 votes
3 answers
24k views

Has AES-128 been fully broken?

Has AES-128 been broken over the full 10 rounds? If so, by what means? By a commercial entity? By a supercomputer? If not, why is AES-256 used to replace AES-128 so frequently?
Offir's user avatar
  • 283
17 votes
3 answers
13k views

After Google's collision attack, is RSA-SHA1 signature still safe?

Google succeeded to get a collision in SHA-1 last year in an attack called shattered. Does this fact make certificates based RSA-SHA1 Signature risky for creating fraud certificates? If RSA-SHA1 ...
adi's user avatar
  • 175
4 votes
5 answers
4k views

Why is a too fast hash function not secure?

I understand why we need hash functions to be fast enough for processing but slow enough for security. But I do not get why a very fast hash function can cause a collision. My guess is that a very ...
Seif Ashraf's user avatar
9 votes
3 answers
18k views

Is it possible to find the key for AES ECB if I have a list of plaintext and corresponding ciphertext?

Assume I have a list of plaintext text and its corresponding ciphertext which was created using a specific key with AES in ECB mode. Can I recover that key? If, how big does the list of plaintext ...
Richard Jones's user avatar
18 votes
1 answer
12k views

In 2020, SHA-1 practically broken in chosen-prefix collision (CP-collision). Can double SHA-1 hashing prevent CP-collision?

In a recent study SHA-1 is a Shambles - First Chosen-Prefix Collision on SHA-1 and Application to the PGP Web of Trust by Gaëtan Leurent and Thomas Peyrin. 2020, they showed the first practical chosen-...
kelalaka's user avatar
  • 48.8k
8 votes
2 answers
2k views

SHA-512 - How difficult is it to find a hash digest beginning with at least twelve zeros?

I know it's possible to find a hash value with multiple zeroes in it, I know of some BitCoin hashes with it, but how difficult is it to find/create a hash digest with 12 or more leading hex zeroes in ...
sha512guest's user avatar
8 votes
2 answers
4k views

Argon2 for both password storage and key derivation

Is using Argon2 for both password storage and key derivation secure? I'm planning on using different salt values, of course. The basic concept is something like this: Alice has some secret data ($...
John's user avatar
  • 83
4 votes
2 answers
3k views

Is it hypocritical to use AES-256 and RSA 2048 in the same application?

I see a common claim that AES-256 is the gold standard and is good future proofing, often in the same wind as "just use 2048-bit keys for RSA". Security documents seem to recommend both AES-256 and ...
Shruggie's user avatar
  • 237
2 votes
5 answers
2k views

Is it theoretically possible to create an unbreakable cipher?

I know this question might sound strange, but is it theoretically possible to create an unbreakable cipher if we don't consider bruteforce? Some of us believe that it is possible to create ciphers and ...
Evan Su's user avatar
  • 449
4 votes
1 answer
2k views

Is Mega.nz encryption vulnerable to brute force cracking by quantum computers?

I am interested in Mega.nz cloud storage. It is using end-to-end encryption. It says that it uses AES-128 to encrypt files And there are more details in their white paper But I saw that quantum ...
le menhir's user avatar
2 votes
3 answers
1k views

3DES security when K1=K3

I am mainly looking for security on 2-key $\operatorname{3DES}$ implementation where $K_1=K_3$. How hard or easy is it to crack $\operatorname{3DES}$ when $K_1=K_3$?
SSA's user avatar
  • 640
1 vote
2 answers
3k views

How weak is using AES with a 128 bit key but 64 bits of the secret key are public constants?

Respected community, I was wondering how weak would AES-128 be, if we provide only a 64 bit key with the other remaining 64 bits either zero bits or public constants, known to the attacker. Is it easy ...
Aravind A's user avatar
  • 1,030
2 votes
2 answers
944 views

80-bit vs 128-bit security in today's world

In today's world of applications, I see a lot of the time a 256-bit encryption key is used, but what about an 80 or 128? What makes 256 the one to use. Is a 80 or 128 easily decrypted? Are comp ...
newJavaCoder's user avatar

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