Call of Duty: Infinite Warfare has an extensive range of weapons and skins to acquire through purchasing Supply Drops. As is typical for this kind of game, you can either grind out these items through playing the game—one rare Supply Drop costs 30 keys, which can typically be earned in about two hours of play time—or you can pony up some cash and buy the Supply Drops directly—a rare Drop costs about $2 when bought with the real money currency “COD Points.”

A flaw over the holiday period allowed Infinite Warfare players to earn tens of thousands of keys in minutes. Developer Infinity Ward had an in-game event giving away free Supply Drops containing various goodies. One of those Supply Drops was a crate containing 30 keys. Players soon discovered that this crate could be opened repeatedly simply by, er, mashing the X button, for 30 keys a press. Players could also accumulate yet another in-game currency, Salvage, in a similar way.

With these thousands or tens of thousands of keys, players could then buy items that would have required thousands of hours or grinding, or hundreds of dollars of COD Points, to buy. Widespread use of the flaw caused Infinity Ward’s parent Activision to disable the game servers temporarily until something could be done.