Visa has dropped Global Payments following the data breach (Andrew Harrer/BLOOMBERG)

Global Payments announced Friday that 1.5 million credit card numbers from its systems may have been exposed after detecting “unauthorized access” into its processing system. Here’s a quick primer on the attack, what the reaction has been and what you can do to protect yourself.

What is Global Payments? Global Payments is a third-party processing company that has clients including financial institutions, government agencies and large corporations. Clients at the time of the breach included Visa and MasterCard.

Who was affected? The company said that 1.5 million records may have been exposed, from Visa and MasterCard.

What was taken? According to the company, while credit card numbers may have been exposed, personal information such as names, addresses and Social Security numbers were “not obtained by the criminals.”

When did it happen? Global Payments detected the breach in “early March,” but has not specified when exactly the attack took place or how it happened.

What’s been done in response? According to the latest statement from Global Payments, the breach has been “contained.” The company said it is working with “industry third parties, regulators and law enforcement to assist in the efforts to minimize potential cardholder impact.” It is also working with security and forensics firms to get to the bottom of the access.

What should I be looking out for? As a cardholder, you should keep an even closer eye on your bank statements to look for unauthorized charges. Investigate and report any anomalies as quickly as possible.

Also, be aware of phishing scams. Keep in mind that no reputable firm will ever ask you to enter your username and password into an e-mail, and any e-mails asking for that information should be deleted immediately.

I think my account’s been compromised. What can I do? If you’re worried about charges you’ve found on your cards, contact your card company immediately. Cards often have a toll-free number printed on them in case of emergency.

You can also put a fraud alert on your credit report to contain the damage from bad charges. Contact the three major credit report companies — Experian, Equifax and TransUnion — to do so.

For more information, or to report a fraud complaint, check out the Federal Trade Commission’s information on credit fraud.

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