Marriott International has announced a massive data breach that exposed approximately 5.2 million hotel guests' information.

According to Marriott International, the breach exposed information such as customers' personal and contact details, loyalty account information, airline loyalty programs, and room preferences.

"Upon discovery, we confirmed that the login credentials were disabled, immediately began an investigation, implemented heightened monitoring, and arranged resources to inform and assist guests," wrote Marriott International.

This is the second major data breach Marriott International has disclosed in less than two years.