A database containing personal data of approximately 533 million Facebook users is freely available on the Internet, of which about 1.3 million come from the Czech Republic. Given that Facebook has 2.8 billion users worldwide and just over five million in the Czech Republic, this is an intervention of approximately twenty percent of its users.
The leak occurred as early as 2019, when Facebook fixed a bug that made it possible to obtain the phone number assigned to a Facebook account. An as yet unknown author then wrote an application that automatically scanned available data about Facebook users and added other published data to the ID (which is public) and phone number (revealed by an error) – name and surname, status, place, date of birth, e-mail address, and has now appeared on the Internet.

How to check if you’re part of the Facebook data breach

One well-known site that tracks data breaches is Have I Been Pwned. Just follow the link to the site and put in your email address or telephone number. You will find out not only if you’ve been part of the Facebook breach, but also any other breaches in which your data may have been compromised.