Our data is sold, redistributed, abused and leaked to our detriment and beyond our control. Knowing it is important to take appropriate actions: change password, and even change email address / phone number.
Internet users can check whether their personal data has been compromised by data breaches by checking them on https://haveibeenpwned.com (HIBP).
The HIBP site has been widely touted as a valuable resource for Internet users wishing to protect their own security and privacy.
How does it work ?
Aggregation of all leaks
The service collects and analyzes hundreds of database dumps and pastes containing information about billions of leaked accounts, and allows users to search for their own information by entering their username or email address.
Users can also sign up to be notified if their email address appears in future dumps.
The notification alerts is a great help. Furthermore, it is absolutely mandatory to have different password for each sites. But having different emails (or alias) might also be a clever idea.