Linked Questions
19 questions linked to/from Attacks of the MAC construction $\mathcal{H}(m\mathbin\|k)$ for common hashes $\mathcal{H}$?
2
votes
1
answer
531
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How secure is MD5 for one way authentication?
I have a server S1 with an Private String (PS) as an identifier shared with a server S2.
Every 10 min S1 publish the hash value of PS+the current time which is used as public identifier (PI). Every ...
- 173
4
votes
1
answer
185
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Does the length extension attack apply to KDFs?
Older hash functions like SHA-256 and SHA-512 are vulnerable to the length extension attack, which is problematic in the context of a MAC. There are several ways to prevent this:
Use a newer hash ...
- 2,120
0
votes
1
answer
92
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What does this protocol mean?
Does this mean that the message is being added onto the hashed(message, tag) ?
m || H(m, "secret")
So the output would be something like:
"RandomMessage"+...
- 69
0
votes
2
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74
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Can the secret and the message be switched in a mac? [duplicate]
A HMAC is usually said to be H(sk || msg) for some secret key sk and message msg.
My first question is, can we compute it as H(msg || sk) instead ? Is there any drawbacks doing it ?
If the answer is ...
- 21