Rabbits sometimes have the name "entity.KillerBunny.name"

I was playing around on a random world, when I found a rabbit with the name entity.KillerBunny.name. It was naturally spawned, and behaved like a regular rabbit, except that when it was at specific coordinates and had a stone block behind it, it would leap towards me as if it were trying to attack me, but it would do no damage. When I started to experiment with this behavior, it stopped happening. When I tried spawning killer rabbits with commands, they acted normally. I tried to find more naturally spawned killer rabbits to see if the same thing happened, but I couldn't.

I will upload the world if someone tells me how to.