Linked Questions
17 questions linked to/from Is it possible to obtain AES-128 key from a known ciphertext-plaintext pair?
4
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1
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Shortcuts / practicality of brute forcing block cipher (AES) + ECB with known plaintext [duplicate]
I know the plaintext (26 bytes long) and cryptotext of block cipher (suspected to be AES) in ECB mode. I can generate hundreds or thousands of such samples, but the samples are not arbitrary. What are ...
0
votes
1
answer
1k
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Is it possible to obtain AES-128 key from a known ciphertext-plaintext-iv tuple used the encrypt the plaintext? [duplicate]
i have a file, which was encrypted with AES-128 in CBC mode. I know the content of original file and know the iv used to encrypt that file.So, just wondering if it's possible to recover the key used ...
0
votes
1
answer
1k
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Is the key deducible with AES CTR when we know about the plaintext, IV and the ciphertext? [duplicate]
Simply as stated, with AES running in CTR mode, can somebody work out the key (without brute-forcing) given we know about the plaintext, IV and also the ciphertext.
Assuming we also know about the ...
0
votes
0
answers
1k
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Aes brute force when part of data known [duplicate]
I have buffer of 16 bytes that encrypt with AES 128 cbc with IV =000000......(all IV is 0)
I have the encrypted buffer, and I know 7 bytes from 16 bytes before the encryption , I dont know the key .
...
1
vote
1
answer
267
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Why can´t an attacker find the key if he has the plain text, the IV and the ciphertext? [duplicate]
I am reading a book about web security and they are now talking about AES CBC.
After reading the chapter I was wondering, can an attacker compute my secret key if he has access to the IV, the plain ...
0
votes
0
answers
440
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Is it possible to recover the key to a decrypted file? [duplicate]
Is it possible to recover the key to a decrypted file if you have the initialization vector and it uses RijndaelManaged in CBC mode? If so how?
The file I want to recover the key from is a xml that ...
2
votes
1
answer
302
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Guessing the key in AES256-GCM? [duplicate]
I assume that my case is weird but I've the following information:
IV: 0x263e or 0x3e26
Auth tag: 0x25
AES256-GCM encrypted payload: 0x4eec96df534ade4c013a
AES256-GCM decrypted payload: ...
-1
votes
1
answer
272
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How dangerous is it to encrypt with AES 256 if the end user knows the unencrypted value? [duplicate]
I am implementing a bit of security in a system that was originally built without encryption on a specific piece of data. The plan was to encrypt this piece of data and include it as part of the ...
0
votes
0
answers
122
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how many pairs of plaintext-ciphertext are needed before we break AES? [duplicate]
Imagine a set of words ($plaintext$) each are encrypted using AES-ECB mode and due to some leakage in the system an attacker could gain access to some pairs of $plaintext$ and $ciphertext$. But once ...
0
votes
0
answers
56
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AES-XTS: find key from ciphertext and plaintext [duplicate]
Let's say I have a plaintext, the corresponding ciphertext encrypted using AES-XTS, and the initialization vectors. Is there any way - not brute force, of course - to compute the key?
Even if there's ...
1
vote
0
answers
36
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Is there a flaw in whole disk encryption vs volume or folder encryption? [duplicate]
My company just implemented whole disk encryption on all laptops (Symantec) and the concept seems flawed. Please correct me if I'm wrong, but if I have known file in plain text and that same file in ...
1
vote
0
answers
25
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Is it possible to crack AES-256 ECB when provided with the ciphertext and a portion of the corresponding plaintext? [duplicate]
AES-ECB encrypts the message by breaking it into blocks and encrypting them one by one. Provided the knowledge of the ciphertext, a portion of the plaintext that corresponds to a block in the message, ...
6
votes
2
answers
2k
views
Does having a known plaintext prefix weaken AES256? [duplicate]
I plan on storing data, encrypted with AES256, where the first dozen bytes are known plaintext. ('Hello World!' for example.)
Does having this known plaintext prefix weaken AES256?
I do not care ...
8
votes
2
answers
19k
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If I have the unencrypted text and the encrypted text, can I calculate the key?
If I have the unencrypted text and the encrypted text, can I calculate the key? It seems logical based on my limited knowledge of encryption that I should be able to... but it also seems like too ...
2
votes
3
answers
5k
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Which attacks can be avoided by the use of OFB instead of ECB?
For a file encryption program, I was told to use Output Feedback mode (OFB) instead of ECB (Electronic code book) mode.
Which attacks can I avoid by this choice?