In 2019, a massive Facebook data leak exposed the personal information of more than 533 million users from over 100 countries. The leaked database later appeared publicly online and quickly spread across hacker forums and breach-sharing communities.
The exposed data reportedly included:
- Full names
- Phone numbers
- Facebook IDs
- Locations
- Birthdates
- Email addresses (for some users)
- Relationship information
Unlike a traditional password hack, this incident involved data scraping through a vulnerability in Facebook’s contact-import feature. Security researchers later confirmed that attackers collected the data before Facebook disabled the vulnerable feature.
How Did the Leak Happen?
The leak was connected to Facebook’s “Contact Importer” functionality. Attackers abused the feature by uploading large numbers of phone numbers and matching them against Facebook accounts. This allowed them to gather user profile information at a massive scale.
Although Facebook stated the vulnerability was fixed in 2019, the collected data resurfaced publicly in 2021 and continued circulating afterward.
How Many People Were Affected?
The breach reportedly impacted users from more than 106 countries. The total leaked records exceeded 533 million accounts. Some estimates included:
| Country | Approximate Affected Users |
|---|---|
| United States | 32 million |
| United Kingdom | 11 million |
| India | 6 million |
| Bangladesh | Thousands of users |
| Other Countries | Millions more |
Why This Leak Is Dangerous
Even without passwords, leaked personal information can still be extremely valuable to attackers. Cybercriminals may use exposed data for:
- Phishing attacks
- Scam calls and SMS messages
- Identity impersonation
- Social engineering
- SIM swap attempts
- Credential stuffing attacks
Phone numbers are especially valuable because they can be linked to messaging apps, banking services, and two-factor authentication systems.
Was Your Data Exposed?
Use our breach monitoring tool to check whether your email address or phone number has appeared in known public data breaches.
Check Your Exposure Now →What Should You Do If Your Data Was Leaked?
1. Enable Two-Factor Authentication (2FA)
Use an authenticator app instead of SMS whenever possible. Recommended apps include Google Authenticator, Microsoft Authenticator, and Authy.
2. Watch for Phishing Attempts
Attackers may pretend to be Facebook, Banks, Delivery services, or Government organizations. Never click suspicious links from unknown messages.
3. Change Reused Passwords
If you reused passwords across multiple websites, update them immediately. Relying on human memory is dangerous.
to generate strong, mathematically unique passwords for every site.
4. Secure Your Network
When reviewing sensitive login alerts or resetting bank passwords on public Wi-Fi, always encrypt your traffic.
Frequently Asked Questions
The incident was primarily described as a large-scale scraping operation utilizing a vulnerable API endpoint, rather than a direct database infiltration.
Public reports indicated that passwords were not part of this specific leaked dataset.
Yes. Phone numbers can be used for phishing, spam campaigns, SIM swap attacks, and account recovery abuse.
Sources: The Guardian (Data Security Report), Tom's Guide, Public Meta (Facebook) Vulnerability Statement.
Expert Security Advisory
If your credentials were leaked in this threat vector, immediately migrate your accounts to an end-to-end encrypted architecture.