According to the Call of Duty patch notes (which can be found below), the Infinite Warfare update makes changes to lots of different multiplayer maps, fixing certain exploits and an issue surrounding win/losses.
The Call of Duty Infinite Warfare update also tweaks Zombies in Spaceland, and makes one or two fixes specifically for PC and Xbox One.
The update arrives just days after it was revealed that Call of Duty: Infinite Warfare was the biggest selling game in September, beating the likes of FIFA 17 and Battlefield 1.
This is despite the fact that launch sales were said to be down on the previous Call of Duty game.