Citi Says Credit Card Customers’ Data Was Hacked

Citigroup acknowledged on Thursday that unidentified hackers had breached its security and gained access to the data of hundreds of thousands of its credit card customers in North America.þþ“During routine monitoring, we recently discovered unauthorized access to Citi’s account online,” the bank said in an e-mailed statement. “We are contacting customers whose information was impacted.”þþThe bank said about 1 percent of its North American credit card holders had been affected, putting the total count of customers exposed in the hundreds of thousands, based on its annual report for 2010, which said it had about 21 million credit card customers in North America.þþWhile information concerning customers’ names, credit card numbers, addresses and e-mail addresses was exposed, the bank said that data like the “social security number, date of birth, card expiration date and card security code were not compromised.”þþ“Citi has implemented enhanced procedures to prevent a recurrence of this type of event,” the bank said. “For the security of these customers, we are not disclosing further details.”þþWhile no group has claimed responsibility for the breach, it is part of a spate of recent cyberattacks.þþSony has reported a series of assaults on its PlayStation network and several Sony Web sites — one hacker site says there have been 18 so far — after the company sued, and then settled with, a programmer who had cracked the PlayStation code. Other attacks have hit PBS, Fox and an F.B.I. affiliate known as Infragard.þþBut none of those breaches appears to pose as direct a threat to consumers as the one reported by Citi. A spokesman for the bank said that only credit card customers had been affected, not debit card holders, and that law enforcement had been alerted.þþThe Financial Times earlier reported the breach.