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Can someone view this video and comment?

https://cipherloc.net/cipherloc-presents-details-of-encryption-attacks/

The concept is presented between 8 and 13 minutes, and then results are presented at roughly 20 minutes, but I think the results are limited to some type of linear cipher.

They claim at 12 minutes that with as little as 5 collisions, a message can be obtained directly. The problem is that I don't see how this is effective against AES. I calculate that the probability of even a single collision occurring for an AES-128 encrypted message--for 1 million blocks in CBC mode-- is roughly 10^-27. Pardon me is my arithmetic is off, but the point remains. In any case this is the basis for which they claim a successor for AES is required...

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closed as unclear what you're asking by Gilles, otus, DrLecter, e-sushi Dec 12 '16 at 12:41

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Unless I am gravely mistaken, they are just talking about CBC information leakage, which is a known result and not a problem for block ciphers with sufficient block sizes, like AES (unless you consider encrypting unrealistic amounts of data under the same key). $\endgroup$ – DiscobarMolokai Dec 11 '16 at 20:38
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    $\begingroup$ Your question should be self-supporting. We should not have to go watch a video somewhere. You need to add more detail. $\endgroup$ – mikeazo Dec 11 '16 at 20:43
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    $\begingroup$ Cipherloc tries to push their own product (PKPA) using mindbogglingly false claims about block ciphers and modes of operation. They're at best utterly clueless, at worst utterly dishonest. $\endgroup$ – Dennis Dec 12 '16 at 3:04
  • $\begingroup$ Not sure how I can re-phrase this without referring to the link, length would be excessive $\endgroup$ – John Dhamas Dec 12 '16 at 16:35
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Without having listened to the lecture, I agree with you. This makes no sense. With AES-128, the probability of getting collisions is very small. There has been a lot of work computing the security of known modes of encryption, and you have to be encrypting an insane amount to have even a reasonable probability of a collision happening. If you are using 3DES then this is a completely different story and indeed 64-bit blocks isn't enough anymore.

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