Not sure this is news or not, but there has been a wall hack leaked recently?
It's wall hack, and there are limitations how they can exploit it. They have to surface out onto the outside when they attack (otherwise the will block off their attacks). However, weapons like TG3's dobergun can reach out without the actually mech exposing itself, as well as bullet-zero whips.
Here's 2 screenshots for proof. I haven't reported it, as it takes me too much effort to type in chinese.. If you want to use this to report tho, you're more than welcome to.