Don’t let cyber-criminals hack your systems.

Staples recently announced that the data breach it has been investigating since October may have compromised over 1.16 million customer credit cards.

Cyber-criminals installed data-stealing malware in 115 store locations across the country, affecting 35 states. This malware may have been used for thieves to gain access to and steal customers’ names, credit card numbers, expiration dates and verification codes. You can see the full list of impacted store locations here.

At all but two of the affected stores, the malware was active from Aug. 10 through Sept. 16. The remaining two stores were impacted from July 20 through Sept. 16. Staples is offering identity theft protection services for those customers who made a purchase at one of the listed stores during the time of the breach. The company is also urging customers to regularly check their financial statements in the days ahead.

“Staples is committed to protecting customer data and regrets any inconvenience caused by this incident,” said the company in its official announcement about the breach. “Staples has taken steps to enhance the security of its point-of-sale systems, including the use of new encryption tools.”

The company is only the latest in a string of retailers to suffer from a massive data breach, following Target and Home Depot. It’s getting more and more crucial for businesses to increase their cyber-security defenses, especially since hackers continue to develop more sophisticated malware strains.

If you own a business, make sure you’re using the most secure point of sale system available, so you can keep your customers’ information protected and secure. It’s much easier to defend against an attack than it is to clean up the messy aftermath of one.