The dust is still setting, but the information on this case currently available, which also includes the official press release, is worrying: Just this Friday, November 30, the hotel chain Marriott International announced that it has become the target of a hacker attack. Marriott's brand names include W Hotels, St. Regis, Sheraton Hotels & Resorts, Westin Hotels & Resorts, and Le Meridien Hotels & Resorts. The compromised database contains personal information about customers, in particular, reservations made in the chain's hotels before September 10, 2018.

Even more worrying are the sheer numbers and the nature and extent of the stored and leaked data. Allegedly it took 4 years for Marriott to discover the problem, which would mean continuous access to this data for that period.  It's data on more than half a billion accounting transactions (>500,000,000 to show only the zeros - this corresponds approximately to the total number of EU citizens), whereby it is conceivable that individual persons appear several times.

According to the press release, the data contained per record includes ‘combinations of name, mailing address, phone number, email address, passport number, Starwood Preferred Guest ("SPG") account information, date of birth, gender, arrival and departure information, reservation date, and communication preferences’.

For a still unclear portion of these records, the record per person is said to also include payment card numbers and payment card expiration dates, but the payment card numbers were encrypted using Advanced Encryption Standard encryption (AES-128).  This is a symmetric encryption method in which the key for encryption and decryption is the same. If this still sounds trustworthy for these particularly critical attributes, the company has determined that both components required for decrypting payment card numbers may also have been stolen at the same time. This suggests that an unknown percentage of the total unknown data pool might be affected. Given the scale of the leak, a significant absolute number of personal profiles with credit card data "in the wild" must be expected.

It is still unclear what role the above-given deadline of September 10, 2018 plays in this context, but at this point, the leak seems to have been closed. The press release reads as follows: "On September 8, 2018, Marriott received an alert from an internal security tool regarding an attempt to access the Starwood guest reservation database in the United States.  Marriott quickly engaged leading security experts to help determine what occurred.  Marriott learned during the investigation that there had been unauthorized access to the Starwood network since 2014."

Building trust must be the foundation of any business strategy.  The first and only starting point is to design corporate strategies in such a way that they are aware of the importance of customer data and the protection of privacy. This involves both well-thought-out business processes and suitable technologies. Of course, this includes trustworthy storage and processing of personal data. Evidence of this must be provided to many stakeholders, including the relevant data protection authorities and the users themselves.  

So first and foremost it is about trust as a central concept in the relationship between companies and their customers. However, the trust of Starwood/Marriott customers could be fundamentally and lastingly destroyed.

The problem with trust is that it needs to be strategically grown over long periods of time, but as it is highly fragile it can be destroyed within a very short period of time. This might be through a data breach just like in this current case. Or through not building adequate solutions. Or not communicating adequately. The real question is why many organizations have not yet started actively building this trusted relationship with their users/customers/consumers/employees. The awareness is rising, so that security and privacy are moving increasingly into the focus of not only tech-savvy users but also that of everyday customers.

Last but not least, as both a European and customer of this hotel chain (and as a layman, not a lawyer), I really would like to ask the following question: The deadlines for reporting a data breach according to the requirements of the GDPR are the latest 72 hours after the breach becomes known. With what we know until now, shouldn’t we have heard from Marriott much earlier and in some different form?