Cybercriminals stole the data of 500 million customers


One of the biggest data breaches ever. In November 2018, the company disclosed that the data of up to 500 million guests who had booked reservations at its properties were compromised after attackers breached its network for at least four years.

The compromised information included names, mailing addresses, phone numbers, email addresses, passport numbers and Starwood Preferred Guest account information. For some customers, the leaked data also included encrypted payment card numbers and payment card expiration dates.

In December 2018, it was reported that investigators had traced the attack to Chinese intelligence-gathering efforts. Though in March 2019 the CEO denied that was the case. By February 2020, the media reported Chinese involvement in this breach again after the Attorney General's announcement of the indictment of Chinese military hackers.

In November 2020, the UK's Information Commissioner's Office ("ICO") fined the company £18.4 million for failing to keep their customers’ personal data secure. The fine levied was considerably reduced due to consideration given to the economic impact of COVID-19 on their business (the ICO initially proposed £99 million back in July 2020). That said, the fine was still in the top 10 of all GDPR fines to date.

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