It wasn't exactly a quiet Christmas Day for Halo this year, as although Halo Studios hasn't got anything to announce right now, some random poster on 4chan decided to leak 90GB worth of content relating to the franchise.
That's according to a report from The Game Post, which mentions that the leak was for the "Halo Digsite Archive" - a resource that modders have previously used to help 343 Industries restore old content from early Halo games.
The person called "John" (seen in the tweet above) used to work on the Halo Digsite project, and advised that nobody is aware of who caused the leak yet, and it actually contains some .dll files that he didn't have access to.
It was a bit of a controversial project amongst some people who worked on it as well, as there never appeared to be a financial incentive - something that John says "is what it is", and that he was doing it simply for the "love of the game".
Anyway, the TL;DR is that a big leak for classic Halo titles has arrived on the internet, and we may start seeing a bunch of leaked content over the coming days and weeks. It doesn't appear that anything relating to the future of the franchise is part of this though - it's mainly focused on everything from Halo 1 up to Halo: The Master Chief Collection.