That makes almost a year of theft before MSG got wise to it, with hackers spiriting away all the data needed to create a replica card. The company said it was notified of a possible breach and started looking into it along with "leading security firms." After spotting unauthorized access, "MSG worked with the security firms to stop it and to implement enhanced security measures," it said. The point-of-sale systems are now safe, but MSG advises customers who visited venues during that period to check their credit card statements for unauthorized purchases.

The company didn't say how many customers were affected, but the number who went to events at those venues is in the millions. It also didn't indicate why it took so long to spot the breach, fix it and report it to the public. The theft reportedly didn't impact online or box office ticket sales, so if you went to the game and didn't buy anything with a credit card, you probably weren't ripped off (at least not by the thieves).