Re: [Cfrg] matching AES security

[Peter Gutmann <[e-mail]>]

Johannes Merkle <[e-mail]> writes:
>The attack is very simple:
>- Gather a list of 2^N cipher texts resulting from the _same_ plain text
>encrypted under 2^N random keys.
>- For 2^(128-N) randomly chosen (different) keys, encrypt the known plain
>text and check if the resulting cipher text matches one of the gathered
>cipher texts

That attack is *conceptually* very simple, in the same way that getting humans
to Mars is conceptually very simple:

- Build a rocket capable of travelling to Mars and back.
- Board rocket and fly to Mars.

Practically, though, some of the steps are a bit tricky.

Peter.