Skyrim’s next DLC named?

Skyrim’s latest DlC Dawnguard just released, but rumors are speculating that Bethesda is working on the next pack for Skyrim. Bethesda trademark for” Hearthfire “back in may but declined to talk about it.  It is rumored that this DLC will feature zombies, I don’t find that surprising many games are featuring zombies in there games what can you say people love zombies!. What do you guys think this DLC will be about?