Just in case you're not alarmed enough to keep a close eye on your credit cards, a security researcher has said that hotel franchises like Marriott were hacked last year to reveal guests' information, CNN reported.

White Lodging, a company that oversees the Hilton, Marriott, Sheraton and Westin hotel chains, among others, apparently suffered a security breach in 2013, according to independent security researcher Brian Krebs.

Hundreds of cards that had been used at Marriott hotels were compromised with fraud but the cases were seemingly randomized, according to Krebs' sources.

"But those same sources said they were puzzled by the pattern of fraud, because it was seen only at specific Marriott hotels, including locations in Austin, Chicago, Denver, Los Angeles, Louisville and Tampa," Krebs wrote.

As it turned out, White Lodging was the string holding all of them together. The Merrillville, Ind.-based company has since started an investigation.

"An investigation is in progress, and we will provide meaningful information as soon as it becomes available," White Lodging said in a statement released Sunday night.

The individual hotel franchises weren't compromised and didn't have control over the breached data.

"We are working closely with the franchise management company as they investigate the matter," Marriott spokesman Jeff Flaherty told CNN. "Because the suspected breach did not impact any systems that Marriott owns or controls, we do not have additional information to provide."

The FBI recently warned retailers to beware of data breaches like the one that compromised around 110 million Target customers last year.

The agency cautioned that more cyber attacks are likely after officials discovered around 20 cases similar to the 2013 Target hacking fiasco, according to Reuters.

Another recent similar data breach was at luxury chain Neiman Marcus. The hacking took place from July 16 to Oct. 30 of last year, exposing 1.1 million customer cards.

UPDATE: A Hilton spokeswoman reached out to AutoWorldNews on Monday night to state that Hilton hotels were not hacked for consumer information. The list of hotels that were likely affected by the data breach can be found here on the White Lodging website.

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