Global hotel chain Marriott has now started allowing people to check if they were a victim of the massive Starwood hack. The company has put up a service which lets guests look up individual passport numbers to see if they were included in the set of unencrypted passport numbers that were leaked last year.

It was confirmed by the hotel chain last month that a data breach last year had resulted in more than five million unencrypted passport numbers being leaked. Data on “fewer than 383 million unique guests” was leaked in the breach, according to Marriott, which included details such as dates of birth, names, postal addresses, genders, email addresses, and reservation information.

It was also revealed later on that over 20 million encrypted passport numbers were stolen as well in addition to 8.6 million unique payment card numbers. Marriott added that only 354,000 cards were active and unexpired when the breach occurred in September.

The checker that Marriott has put up is hosted by a security firm called OneTrust. Users will be required to provide some personal information such as name, email addresses, and the last six digits of their passport number. It will return a result immediately. Users will have to wait in order to receive a response and Marriott hasn’t said how long that’s going to take. It seems a bit ironic that users will have to provide more personal data just to find out if their personal data was leaked in a breach.

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