Cipher Block Chaining MAC (CBC-MAC) is a method of building a message authentication code from a block-cipher.

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Difference between CBC-MAC and CMAC

According to Wikipedia, CMAC is based on a variation of CBC-MAC and fixes some security deficiencies in it. However, I could not find a simple and clear explanation of what the differences between ...
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Why does CBC-MAC need prefix-free inputs to be a good PRF?

In the FFX spec, there is a note about using CMAC as the round function. Security notes. The round function F is constructed in such a way that the set of inputs on which the CBC-MAC is ...
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Why does only length prepending improve the security of CBC-MAC

I know that length prepending improves security of CBC-MAC. However, wouldn't inserting the length elsewhere (middle, end or any other part of message) be equally good? After all, even the length is ...
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OMAC/CMAC constant for different block sizes

OMAC/CMAC only specifies constants for 64-bit (0x1B) and 128-bit (0x87) block size. I would like to know how to get constants ...
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CBC-MAC , fixed length, all blocks returned

CBC-MAC, with fixed length message. Is it safe to return all ciphered blocks instead of the last? My intuition says it is less secure, since is gives an attacker more information. But how could one ...
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Distinguishing attack on CBC-MAC

I want to ask about distinguishing attack on CBC MAC, as in the paper published by Ketting Jia, Xiaoyun Wang, Zheng Yuan, and Guangwu Xu: Distinguishing Attack and Second-Preimage Attack on the ...
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Modifications of CBC-MAC

I'm preparing myself to exam, but I have a lot of troubles with rigorous proofs. This post is very long, but this is because I remind here 2 long definitions. At the beginning I want to remind the ...
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Is CBC mode encryption vulnerable to a reordering attack?

I know that, if CBC-MAC is used in such a way that the tag is the concatenation of all the blocks' outputs (and not just the last one), it's insecure under CPA for the simplest case of 2 blocks ...
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How to verify a shared secret using only AES?

I have two devices that need to verify that they both are in possesion of the same secret key. One of the devices is a very limited embedded device that only has AES128 available, no SHA or other hash ...
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CBC-MAC forging textbook question

I found this question about CBC-MAC forging and want to make sure I understand it: Let a and be be two strings of block length one. Suppose the sender sends (a, CBC-MAC(a)), (b, CBC-MAC(b)), (a||b, ...
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Question about CBC-MAC

I found this question from a textbook but I don't really understand what it is asking: Suppose $c$ is $1$ block long, $a$ and $b$ are strings that are a multiple of the block length, and ...
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What block cipher is used for CBC-MAC?

What block cipher is used for CBC-MAC? DES, AES, 3DES? Or it doesn't matter?
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Why use CBC-MAC? Why not just apply hash function on the whole message?

Why not just apply hash function on the whole message? Why convert that message into blocks and hash those blocks? To avoid collisions?
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Distinguishing Attack on CBC-MACs

I want to ask again about distinguishing attack on CBC MAC, based on the paper published by Ketting Jia, Xiaoyun Wang, Zheng Yuan, and Guangwu Xu: Distinguishing Attack and Second-Preimage Attack on ...