Another day, yet another retail security breach.
Embattled retailer Sears said on Wednesday it found a security breach involving "unauthorized" credit card activity following some customer purchases at its Kmart stores. It's the second major security breach for the retailer in under three years.
Hackers appeared to infiltrate payment data systems with malicious code that was undetectable by existing antivirus systems, Howard Riefs, a spokesman for Sears Holdings, told NBC News. Once Kmart became aware of the code, Riefs said it was removed and the security breach was contained.
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"Given the criminal nature of this attack, Kmart is working closely with federal law enforcement authorities, our banking partners, and IT security firms in this ongoing investigation," the company said in a statement. "We are actively enhancing our defenses in light of this new form of malware. Data security is of critical importance to our company, and we continuously review and improve the safeguards that protect our data in response to changing technology and new threats."
Kmart said no personally identifying information was included in the breach; however, certain credit card numbers may have been compromised, making it important that customers monitor their statements.
The company has set up a dedicated webpage with more information for concerned customers. Shoppers can also call a customer care hotline at 1-888-488-5978.
Robert Siciliano, CEO of IDTheftSecurity.com, told NBC News that "a lot has happened in the past decade in regards to credit card fraud."
While Sears said it has contained the breach, Siciliano said it's a good reminder to set up additional safeguards for monitoring your accounts.
"Consumers' only option is to pay close attention to their credit card statements each month or to sign up for real-time text and email alerts and notifications via your card company's website or mobile application," he said.
That may mean receiving a text every time your credit card is used for a purchase over a certain amount you set. While these types of alerts can be frequent if you regularly use your card, Siciliano said they're a great way to ensure your payment information isn't being used by someone else.
If your card is used for an unauthorized purchase, you may not be liable if it's promptly reported, making it that much more important to keep an eye on your monthly statements.