All Questions
Tagged with length-extension sha-1
10 questions
2
votes
1
answer
165
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Is the padding wrong on the "Length Extension Attack" Wikipedia page example?
In the Length extension attack of Wikipedia
The following information summarizes the relevant information provided on the page at the time of posting this question.
The provided parameters are
secret ...
- 123
2
votes
1
answer
347
views
How can Hashed Value be same in length extension attack?
Let's say we had the following information:
Secret = "Hello"
Message = "Attack at Dawn"
H(s,m) = ABC
Alice is sending a message to Bob but there is a person in the middle, ...
1
vote
1
answer
844
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is MAC double-hashing enough to prevent length extension attacks?
I know that
$$mac=\operatorname{SHA1}(secret\mathbin\|message)$$
is prone to length extension attacks, but what about:
$$mac=\operatorname{SHA1}(\operatorname{SHA1}(secret\mathbin\|message))?$$
In ...
- 569
4
votes
2
answers
1k
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The length extension attack and security on length shortening of a hashed message by one byte
MD5, SHA1, SHA2 are vulnerable to length extension attacks Wikipedia:Length extension attack.
Could is also be possible to generate $H(\text{message}[1..n-1])$ from $H(\text{message}[1..n])$ if I know ...
- 151
2
votes
1
answer
3k
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Length Extension attacks in SHA1 and MD5?
From my understanding on the internet about length-extension attack, I have understood that hash(secret_key|known_data) can be exploited to produce hash(secret_key|known_data|appended_data) even ...
- 43
0
votes
1
answer
140
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Equal hashes for different messages when doing key length extension attack sha1
I was doing the cryptopals challenge 29, and I found something weird.
When I try to create a forged hash for a forged message I get always the same hash for different forged messages.
...
2
votes
1
answer
1k
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SHA1 padding on length extension attack
I was recently trying to replicate a length extension attack on SHA1. I implemented the registers state and also the new padding implementation (with the whole of the message that I want to extend). ...
- 21
2
votes
0
answers
753
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Is it possible to prevent length extension attacks
Is it possible to prevent length extension attacks without using any other hash algorithm than SHA-1?
4
votes
1
answer
180
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Is it possible to work out the hash using length extension attack but with different hashes type?
For example, I have:
Unknown: A secret variable, lets call it secret, that is unknown to me
Known: The length of secret, (lets ...
- 51
2
votes
0
answers
56
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Will length-extension work if secret is not prefixed but appended to the data? [duplicate]
Possible Duplicate:
Why is h(m||k) insecure?
Length-extension allows to append any data to the message while not knowing the secret. Any length-extension explaination one the web considers the ...
- 21