The credit card giant said its security division detected multiple instances of fraud that tracked back to CardSystems Solutions Inc. of Tucson, Ariz., which processes transactions for banks and merchants.

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NEW YORK — A security breach of customer information at a credit card-processing company could put at risk 40 million cardholders of all brands, MasterCard International Inc. said today.

The credit card giant said its security division detected multiple instances of fraud that tracked back to CardSystems Solutions Inc. of Tucson, Ariz., which processes transactions for banks and merchants.

MasterCard said in a news release late Friday afternoon that it was notifying its card-issuing banks of the problem.

CardSystems was hit by a computer virus that captured customer data for the purpose of fraud, said company spokeswoman Sharon Gamsin.

MasterCard, which said about 14 million of its own cards were exposed, said it was giving CardSystems a “limited amount of time to demonstrate compliance with security requirements.”

CardSystems officials did not immediately return telephone calls seeking comment. Nor did officials from American Express and Visa.

The breach is the latest in a series that has hurt a number of high-profile companies — including Citigroup Inc., Bank of America Corp., and DSW Shoe Warehouse.

Earlier this month, Citigroup said United Parcel Service had lost computer tapes with sensitive information from 3.9 million customers of CitiFinancial, a unit that provides personal and home loans.