US hospitality giant Marriott International has admitted the stolen passport numbers of over five million guests were not encrypted . Intelligence experts note that American intelligence agencies often seek the passport numbers of foreigners they are tracking outside the United States, which may explain why the United States government has not insisted on stronger encryption of passport data worldwide. The cyber attack was not as extensive as initially thought , with up to 383 million records comprised rather than a suggested 500 million , but the failure of Marriott - owned Hilton Hotels to protect the passport data of guests gave the hackers important tracking information . While 20.3 million passport numbers encrypted , 5.25 million were not . The hotel chain is now looking into universal encryption of passport information and will pay the costs of a new passport if the information is used fraudulently .
US hospitality giant Marriott International has admitted the stolen passport numbers of over five million guests were not encrypted . The cyber attack was not as extensive as initially thought , with up to 383 million records comprised rather than a suggested 500 million , but the failure of Marriott - owned Hilton Hotels to protect the passport data of guests gave the hackers important tracking information . While 20.3 million passport numbers encrypted , 5.25 million were not . The hotel chain is now looking into universal encryption of passport information and will pay the costs of a new passport if the information is used fraudulently .