Often called Greytiders, Griefers, trolls, etc etc.
Naming aside, these are typically identified when you see bald/black-haired default dance humans in grey assistant/visitor jumpsuits. Be extremely wary of them.
They also have bland or randomly generated names.
One broke my leg once and sent me feral in underneath 30 seconds, and yes, I'm still salty about it - Nysku.