Linked Questions
45 questions linked to/from How reassuring is 64-bit (in)security?
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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 ...
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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?
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2
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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 ...
- 101
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1
answer
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Can we have an asymmetric key in AES? Clarification about PBKDF2 and AES-GCM in WebCrypto
Can we have an asymmetric key in AES? Clarification about PBKDF2 and AES-GCM in WebCrypto
According to wikipedia AES page, AES is a symmetric-key algorithm.
The algorithm described by AES is a ...
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4
votes
1
answer
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Partial known message pre-image attack on SHA-1
If the last $448$ bits of a SHA-1 block input are known and only the first $64$ bits are unknown, is it possible to do a preimage attack using SAT solvers or something else? Or do I have to brute ...
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4
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How long would it take all of the supercomputers or cloud computing on Earth to bruteforce a significantly long password?
I was arguing with a colleague who thinks that SHA256 (password + 64 character static salt) is "insecure." My argument is that nothing in cryptography is "secure," it's all a ...
- 138k
1
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1
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KEY using AES-128, If P is less than 128 bits, padded with 0 and create 128 bits, any problem if average pw length is 6
For communication between the client and the website, use password (P) as the key using AES-128. If P is less than 128 bits, it is padded with 0 to create a 128 bits key. is there any problem with ...
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1
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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 ...
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1
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2
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Recovery Passphrase Collission for BIP-39 and BIP-44
Referring to the standards of [BIP-39] and [BIP-44]: a 'master password' consisting of 12 words uniformly selected from a 2048-word dictionary corresponds to 128 bits of entropy, that is then used as ...
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Which passphrase length is good so it's hard to break bitcoin's PBKDF2 key?
According to https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki#From_mnemonic_to_seed
To create a binary seed from the mnemonic, we use the PBKDF2 function
with a mnemonic sentence (in ...
- 47.6k
4
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5
answers
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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 ...
- 138k
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0
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Finding the cleartext password given its MD5
Given powerful GPU and PC hardware, is it realistic to recover a password in a few hours given a cleartext's MD5? Max chars are 95, and the maximum length of the password is 15 characters.
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MD5 hash: retrieve an element of a source string
Suppose you have a string, precisely an MD5 hash string, which basically it is computed in the following way:
"element1:element2:element3"
So, in order to get ...
- 47.6k
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2
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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 ...
- 47.6k
1
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2
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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 ...
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