[Gameplay] Baron Nashor Corrosion/Corruption Range

This could very well be working as intended, but in a game I was spectating a Bard was standing behind the wall of the Baron pit, and the corrosion debuff stacks were being applied, as well as the damage (he died from this, as the jungler, preventing a pretty easy baron steal). Is the range on Baron's debuff abilities supposed to extend beyond the wall of the pit?