Just had the same issue here, I encountered it just pass the entrance to the goblin camp (snuck around the side of it and attacked the three goblins sitting around a table). Familiar will instantly initiate combat and count as hostile (however only to the character that summoned it, no one else is able to attack it) despite it still being under full player control. This appears to happen with any type of familiar (unable to test with Warlock ones as this is happening on my Ranger) no matter the location. Familiars (including Warlock ones on a different character) have worked fine up until this moment.
