I am 100% positive that if you are caught using bugged gear (that gives you an advantage) it is considered an exploit and you can be banned from the game.
There are times that bugs occur in the favour of the player that SSG (formerly Turbine) knows about but cannot expect players not to use, and thus allows players to continue with them until a patch corrects them.
Ex. If there was a bug that gave Challenge 25 targets they could not expect Guardians to stop using the skill.
It is also against the CoC to share info with others about the exploit, thus promoting it.
You should send in a bug report via the in game help menus.