The Marriott Data Breach – How Hackers Accessed Half a Billion Guest Records

In 2018 Marriott International revealed that hackers had breached its Starwood guest reservation database, compromising personal information of approximately 500 million guests. This incident was one of the largest data breaches in history and exposed the vulnerabilities in even the most established global corporations.

The breach began in 2014 but went undetected until 2018. Attackers gained unauthorized access to the Starwood network by exploiting weaknesses in the company’s security infrastructure. Once inside, they maintained persistent access to the system for years, collecting sensitive data from guest reservations across many Marriott properties worldwide.

The stolen data included names, mailing addresses, phone numbers, email addresses, passport numbers, and even encrypted payment card details. The long duration of the breach increased the scope and impact, exposing millions of guests to potential identity theft and fraud.

Marriott faced extensive public backlash along with investigations and fines from regulatory bodies around the world. The company committed to strengthening its cybersecurity measures and improving detection capabilities to prevent future breaches.

This attack demonstrated the importance of continuous monitoring and timely incident detection. It also showed how mergers and acquisitions can introduce new cybersecurity risks if proper integration and security audits are not performed. Moreover, the breach highlighted the value of encrypting sensitive data to reduce the damage when systems are compromised.

Hackers in this case used sophisticated tools and techniques to remain undetected over a long period. Their ability to blend into the network and avoid triggering alerts stressed the need for advanced threat hunting and behavioral analysis in cybersecurity defenses.