Source

NEW YORK - The names, banks and account numbers of up to 40 million credit card holders may have been accessed by an unauthorized user, MasterCard International Inc. said Friday. The credit card giant said the security breach involves a computer virus that captured customer data for the purpose of fraud and may have affected holders of all brands of credit cards.
The crux of the issue is that the breach my be used for theft of funds but not, thankfully, ID theft.

I find it interesting that the FBI told the company that actually lost the data to be quiet but Mastercard itself went public.