6.7 Rengar bug

I was playing a game with Pantheon and had an opponent Rengar , at about 25 minute, he had baron buff, blue buff and when I tried to stun him, his champion bugged, and cast all his spells without cooldown. We managed to kill him but his bug remained, untill the time I stunned him again.

I think it was good to report it here, but I dont know what section I should post it..