https://www.bleepingcomputer.com/news/security/marriott-data-breach-affects-500-million-starwood-guests/

Marriott announced today that their has been unauthorized access to the Starwood guest reservation database since 2014. It is not known how the system was hacked, but up to 500 million guests may be compromised.

The information accessed by the attackers includes the guest name and possibly physical and email addresses. For 327 million people, however, the exposed data also contains the passport number, Starwood Preferred Guest (SPG) account details, date of birth, gender, arrival, and departure information, reservation date, and communication preferences.