George Malandrakis

An upcoming $1000 challenge for cryptographers
I would never call myself a cryptographer, not even an amateur one, but I know one thing for sure: a good encryption algorithm is one that, even if you have dozens of examples of documents and their encrypted versions with the very same key, and one encrypted document, you will not be able to infer the key and decrypt it.

So far I have crafted a couple of simple, if not childish, encryption algorithms, mostly as exercises to learn new programming languages (here is one example). Then there was one slightly better than those. And I am currently working on an encryption algorithm, whose purpose is to be used in a challenge: even with dozens of examples of documents and their encrypted versions with the same key, the attacker should not be able to decrypt the final document -at least not without brute force.

Once the algorithm is ready and this page is updated, you may join the "contest" to decrypt it by writing your name and e-mail in a Google form I will post here, along with a poll for the social media platform where we will all join a common chatroom.

I will then be posting my algorithm along with an archive with about a dozen examples, and the unencrypted file. The ones interested will be able to buy up to fifty extra examples, $2 each. You have one week to deduce the key. The first person to infer the key with cryptanalysis (brute force is not allowed) and decrypt the file will receive $1000 from me. If no one succeeds, I am publishing it (and keeping the money!).

Since crafting this algorithm is something I engage in on and off on my spare time, I would not suggest that you hold your breath until the time for the "contest" has come. It will most likely take months (as of 7/2025). But if someone who is interested contacts me, I may hasten a little bit.