The ciphertext-only-attack tag has no wiki summary.
2
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1answer
92 views
Attacking historical ciphers methodology
It's more a theoretical question of how would you approach it. All you know about the ciphertext it's was generated with a historical cipher. The ciphertext appears to be random, BUT it's divided into ...
6
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2answers
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For public-key encryption, why does COA resistance imply CPA resistance?
My professor told me:
If a public-key crypto-system is secure against ciphertext-only attacks,
then it is also secure against a chosen-plaintext attack.
Why is this true? Is there a proof that ...
7
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2answers
545 views
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 ...