A brute-force attack is attempting to find a secret value by trying all possible values until the correct one is found.
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How much would it cost in U.S. dollars to brute force a 256 bit key in a year?
I am often told that any key can be broken and that it is only a matter of time and resources for any key to be broken. I know that this it technically true. However, I think that there is probably a ...
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How long does it take to crack DES and AES?
Suppose that a single evaluation of a block-cipher (DES or AES) takes 10 operations, and the computer can do $10^{15}$ such operations per second.
How long would it take for to recover a DES key, ...
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2answers
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How can I do a brute force (ciphertext only) attack on an CBC-encrypted message?
Given a CBC ciphertext and IV, how can I find the encryption key?
We are limited with an 8 chars key, each char in the range of [a..h], so I can generate every possible key (these are only $8^8 = ...
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1answer
557 views
Duration for attacking Two-Key Triple-DES Encryption using all RAM ever built?
I am considering attacks on Two-Key Triple-DES Encryption assuming $2^{32}$ known plaintext/ciphertext pairs (that's a mere 32 Giga Bytes of ciphertext) by the method devised by Paul C. van Oorschot ...
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3answers
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Is there some way to generate a non-predictable random number in a decentralised network?
Is there a way to generate a random number with given restrictions:
It will be used in a decentralised network with a big number of peers (no central authority to generate it)
Its generation should ...
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2answers
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Brute forcing CRC-32
I'm working on a cryptosystem which uses IDEA. The designer made the mistake of including a CRC-32B hash of the password unencrypted in the header, so that the system can quickly reject bad ...
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2answers
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Measuring entropy for a ciphertext only attack
When bruteforcing a password (e.g. the common attacks on DES), where you have ciphertext only, you need a way to assess whether a decrypted plaintext is the right one. I believe the EFF DES machine ...
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1answer
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chaining rsa with ecies
In an answer to a previous question it was suggested that one way to protect your asymmetrically encrypted AES-256 keys, from say a solution to prime factorization, would be to chain asymmetric ...
