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LLL lattice reduction is the same algorithm that can be used for cracking PuTTY keys from biased nonces from the CVE a few days ago. 'tptacek explained a bit about the attack (and links to a cryptopals problem for it, which I can almost pretend to understand if I squint) https://news.ycombinator.com/item?id=40045377

In a similar vein, the SciCraft minecraft server had a creeper farm which used some sort of black magic setup in order to deterministically manipulate an RNG state to trigger a "random" lightning strike at a specific block every frame in order to get better creeper drops. https://youtu.be/TM7SutJyDCk




Sean and Kelby do a much better job of describing what LLL is, but this is maybe the best explanation of why LLL is that I've ever read. In all three cases, you only need basic linear algebra, if that (Kelby wants you to grok Gram-Schmidt, which is like just before the midterm of an undergrad linear algebra 101).

I really don't have words for how great this post is. It made my week.

Later

A really concise explanation of the same process you can step through in Python:

https://crypto.stackexchange.com/questions/37836/problem-wit...


Personally I think https://crypto.stackexchange.com/a/86548 is a better answer. It turns the LCG state recovery into a hidden number-like problem, and works out the solution that way. It is easy to go from there to (EC)DSA key recovery.


There is also some Rng manipulation to make blocks always drop the maximum, explained here:

https://youtu.be/ZcdN1wCJPqM?t=390


> some sort of black magic

> which I can almost pretend to understand if I squint

This is me and all cryptography :D




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