NEW YORK (TheStreet) -- Shares of Marriott International  (MAR) were higher in mid-morning trading today despite the Bethesda, MD-based hospitality company and other hotels operated by HEI Hotels & Resorts being breached by malware that may have leaked card payment data.

A total of 20 hotels, including the systems of Hyatt (H), Starwood Hotels & Resorts Worldwide (HOT) and InterContinental Hotels Group (IHG), were discovered to have malware that possibly divulged information surrounding tens of thousands of food, drink, spa and lobby shop transactions, Reuters reports.

The malware affected 12 Starwood hotels, six Marriott properties, one Hyatt hotel and one InterContinental Hotels location, HEI said in a statement. It's unclear how many customers were affected because they may have used their cards multiple times, HEI added. 

The breach was discovered in mid-June, but the malware was active in the system from March 1, 2015 to June 21, 2016, with 14 of the hotels affected after Dec. 2, 2015, HEI said in a statement. 

Hackers may have stolen customer names, account numbers, payment card expiration dates and verification codes, HEI added. HEI has since installed a new payment processing system that's separate from other parts of its computer network.

Shares of Hyatt and Starwood Hotels were up in mid-morning trading today. InterContinental Hotels stock was lower in mid-morning trading on Monday.

Separately, TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this articles's author. TheStreet Ratings has this to say about the recommendation:

We rate MARRIOTT INTL INC as a Buy with a ratings score of B-. This is driven by some important positives, which we believe should have a greater impact than any weaknesses, and should give investors a better performance opportunity than most stocks we cover. The company's strengths can be seen in multiple areas, such as its growth in earnings per share, revenue growth and increase in net income. We feel its strengths outweigh the fact that the company shows weak operating cash flow.

You can view the full analysis from the report here: MAR 

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