Marriott, Hyatt guest data may have been hacked

If you've stayed in a hotel between March 1, 2015 and June 21, 2016 and paid with a card, you might want to sit down before reading this. There was a data breach at 20 HEI Hotels & Resorts-operated hotels in the U.S. — meaning customers at Starwood Hotels & Resorts Worldwide (ticker: HOT), Marriott International (MAR), Hyatt Hotels Corp. (H) and InterContinental Hotels Group (IHG) could be affected, reports Reuters.

A spokesman for HEI, a private company, tells Reuters that malware was found in restaurant, bar, spa and lobby shop payment systems in early to mid-June at these locations; it hit 12 Starwood hotels, six Marriott locations, and one hotel each for Hyatt and Intercontinental. It was also found in additional operations at these locations. The exact number of those affected is unclear because customers could have used cards on more than one occasion. Fourteen were hit after Dec. 2, 2015, according to HEI's website.

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Hackers could have access to names, account numbers, expiration dates and verification codes, though seemingly not PIN code information (HEI's system didn't gather this information), according to HEI.

There were approximately 8,000 transactions at the Hyatt Centric Santa Barbara hotel in California during the time of the breach.

Specifically, Starwood's Westin locations in Minneapolis, Philadelphia, the District of Columbia and more were part of the breach, in addition to Starwood-owned locations in places like San Francisco, Miami, and Nashville, Tennessee, reports Reuters. The Marriott locations involved were in Boca Raton, Florida; Dallas-Fort Worth, Texas; Chicago; San Diego and Minneapolis.

The company put a new payment processing system in place and reported the breach to federal authorities, reports Reuters.

Marriott is currently in the process of acquiring Starwood, though that could have hit a roadblock due to an antitrust law decision in China, reports Seeking Alpha.

On Wall Street, the hotel industry is having a good year. MAR stock is up about 7.3 percent; HOT up 21.4 percent; H up 11.9 percent; and IHG up about 11.8 percent. This breach could certainly knock down some investor confidence, though as Reuters notes, it comes after recent similar breaches at Hyatt and Starwood.

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