Marriott provides update on Starwood database security incident – approximately 8.6 million encrypted payment cards were involved

Marriott is providing an update on the number of guests whose passport numbers and payment card numbers were involved in the Starwood reservations database security incident announced by the company on November 30, 2018.

Working closely with its internal and external forensics and analytics investigation team, Marriott determined that the total number of guest records involved in this incident is less than the initial disclosure. Also, the number of payment cards and passport numbers involved is a relatively small percentage of the overall total records involved.

Marriott is updating its press release of November 30, 2018, which announced that the company determined on November 19, 2018 that there was unauthorized access to a Starwood guest reservations database. In that release, the company said that it believed the incident involved information about up to approximately 500 million guests who made a reservation at a Starwood property* on or before September 10, 2018, although at that point the company had not completed the analytics work to identify duplicative information.

Update on the Number of Guests Involved

Marriott now believes that the number of potentially involved guests is lower than the 500 million the company had originally estimated. Marriott has identified approximately 383 million records as the upper limit for the total number of guest records that were involved in the incident. This does not, however, mean that information about 383 million unique guests was involved, as in many instances, there appear to be multiple records for the same guest. The company has concluded with a fair degree of certainty that information for fewer than 383 million unique guests was involved, although the company is not able to quantify that lower number because of the nature of the data in the database.

Passport Information Update
Marriott now believes that approximately 5.25 million unencrypted passport numbers were included in the information accessed by an unauthorized third party. The information accessed also includes approximately 20.3 million encrypted passport numbers. There is no evidence that the unauthorized third party accessed the master encryption key needed to decrypt the encrypted passport numbers.

Payment Card Information Update
Marriott now believes that approximately 8.6 million encrypted payment cards were involved in the incident. Of that number, approximately 354,000 payment cards were unexpired as of September 2018. There is no evidence that the unauthorized third party accessed either of the components needed to decrypt the encrypted payment card numbers.

While the payment card field in the data involved was encrypted, Marriott is undertaking additional analysis to see if payment card data was inadvertently entered into other fields and was therefore not encrypted. Marriott believes that there may be a small number (fewer than 2,000) of 15-digit and 16-digit numbers in other fields in the data involved that might be unencrypted payment card numbers. The company is continuing to analyze these numbers to better understand if they are payment card numbers and, if they are payment card numbers, the process it will put in place to assist guests.

Starwood Reservations Database Discontinued
The company has completed the phase out of the operation of the Starwood reservations database, effective the end of 2018. With the completion of the reservation systems conversion undertaken as part of the company’s post-merger integration work, all reservations are now running through the Marriott system.