Hackers gained access to as many as 40 million credit and debit cards used by customers of Target during the height of the holiday shopping season, the company reported Thursday, in one of the biggest data breaches in history.
Company officials offered few details on the intrusion, which reportedly began the day before Thanksgiving (Nov. 28) and lasted until Sunday. Security experts said that the kind of information stolen — including names, card numbers, expiration dates and three-digit security codes — could allow criminals to make fraudulent purchases almost anywhere in the world.
The breach highlighted vulnerabilities in the massive, interconnected shopping systems used for billions of dollars of retail transactions every day. Customers at Target's nearly 1,800 stores in the United States were potentially affected, though those who shopped online were not, the company said.