An exploit in World of Warcraft recently enabled a group of hackers to wreak havoc on large cities across a number of servers. The hackers were able to massacre entire cities unimpeded for nearly four hours, killing all players and non-player characters (NPCs) at will.

It is believed that the exploit gave the attackers game master (GM) powers which include the ability to override agreed upon duels and use instant-death skills to perform one-shot kills. We are hearing that busy cities like Orgimmar and Stormwind were targeted across nearly half a dozen servers including Draenor, Ragnaros, Tarren Mill, Tichondrius and Twisting Nether.

It’s possible that WoW expansion pack Mists of Pandaria introduced the new exploit. Alternately, it could have been present for some time and only used sparingly as to remain under Blizzard’s radar.

A member of OwnedCore has already claimed responsibility for the hack. As part of a lengthy discussion on the topic, member Jadd said his team didn’t do any permanent damage and noted that some people thought it was funny to watch. He believes that Chinese gold selling companies are ruining the game, not people like him. Those who didn’t enjoy the attacks should blame Blizzard for not fixing it faster, he said.

Blizzard representative Nethaera says the exploit has already been fixed and should not be repeatable. They are conducting a full-scale investigation into the matter and encourage anyone with information to contact them via email.