Oh hey, this rant of mine is making the rounds.
After I wrote this, one of the Matrix leads commented on it, which prompted me to look at their code. I have since found, uh, 4 3 different cryptographic issues in Matrix's Olm and Megolm code.
Expect a blog post on Dhole Moments at some point in August.
One of them is extremely bad, and will put a lot of burden on Matrix users to mitigate effectively. False alarm: I was mistaken about this one. I'll include it in the write-up, though.
