Last Updated: January 2026
Introduction
In 2021, a dataset containing personal information from approximately 533 million Facebook users across 106 countries was publicly shared online. If you have ever used Facebook with your real name or phone number, assume that criminals already have access to at least some of your personal data.
This was not a traditional password hack. Instead, attackers scraped user data through a Facebook platform vulnerability that existed in 2019. Although Facebook fixed the issue that year, the harvested data resurfaced in 2021 and is now permanently circulating in criminal databases.
The Bottom Line
This guide explains exactly what happened, what data was exposed, and the three actions you must take now to reduce the risk of account takeover, SIM swapping, and targeted scams.
We are not here to debate Facebook’s intent. We are here to make sure you are protected.
🧠 At‑A‑Glance: Breach Intelligence
| Detail | Information |
|---|---|
| Leak Publicly Released | April 2021 |
| Vulnerability Period | Exploited before August 2019 |
| Users Affected | ~533 million (106 countries) |
| Data Exposed | Names, phone numbers, Facebook IDs, birthdates, locations, limited emails |
| Passwords Stolen | ❌ No |
| Financial Data | ❌ No |
| Risk Level | High (phone numbers + identity data enable scams and SIM swapping) |
What Happened? (Brief & Specific)
Before August 2019, attackers abused Facebook’s contact‑import and profile lookup features to automatically scrape public and semi‑public user data at massive scale.
Facebook fixed the vulnerability in 2019, but did not notify affected users. In April 2021, the complete dataset was posted on hacking forums for free, instantly making it accessible to scammers, phishers, and fraud groups worldwide.
Although Facebook describes this as “old scraped data,” the risk remains active because personal data does not expire.
What Data Was Exposed? (Exact Inventory)
Based on verified samples and disclosures, the following information was exposed:
- Phone numbers (primary risk factor)
- Full names
- Facebook user IDs
- Birthdates
- Locations (city and country)
- Gender and profile information
- Employer and relationship status (in some records)
- Email addresses (limited percentage of users)
What Was Not Exposed
- Account passwords
- Credit card or banking information
- Private messages
⚠️ Even without passwords, phone numbers combined with identity data are extremely valuable to modern criminals.
Why This Leak Is Dangerous (Threat Mapping)
This breach is dangerous because of how criminals combine this data with other leaks and real‑world manipulation.
1. SMS Phishing (Smishing)
Attackers send text messages using your real name and location, making scams appear legitimate.
Example:
“Hi Alex from New York, your delivery couldn’t be completed. Confirm here.”
2. Caller ID Spoofing
Scammers impersonate Facebook, banks, or government agencies while already knowing your personal details, increasing trust and compliance.
3. SIM Swapping (Highest Risk)
With your phone number, birthdate, and location, attackers impersonate you to mobile carriers and transfer your number to their SIM.
Once successful, they can:
- Receive your SMS codes
- Reset email and banking passwords
- Drain crypto wallets
4. Targeted Social Engineering
Because Facebook data reveals employers, relationships, and social circles, attackers craft highly personalized scams that bypass skepticism.
Your Action Plan (Do This Now)
✅ Step 1: Check If You Were Affected
Use our Breach Check Guide to verify exposure using trusted breach databases.
👉 Check both your email address AND your phone number. Many users mistakenly check only email and miss phone‑based exposure.
🔐 Step 2: Lock Down the Right Attack Surface
Because phone numbers were exposed, your mobile account is now a critical security boundary. For a full defensive walkthrough, see:
👉 https://pixeldefence.com/how-to-prevent-identity-theft-guide/
Protect Your Phone Number (Priority #1)
Contact your mobile carrier and:
- Add a carrier account PIN or passcode
- Enable port‑out protection
- Turn on alerts for account changes
These steps block the majority of SIM‑swap attempts.
Stop Using SMS for Two‑Factor Authentication
SMS‑based 2FA becomes unreliable once your number leaks.
Switch to app‑based authentication:
- Google Authenticator
- Microsoft Authenticator
- Authy
👉 Follow our 2FA Migration Guide (Phase 2)
Protecting yourself with Authenticator apps is wise, but if you see an invalid code after transfer, follow this troubleshooting guide.”
Change Critical Passwords
Even though passwords weren’t leaked here, attackers combine this data with passwords from other breaches.
Change passwords for:
- Email accounts (master keys)
- Banking and financial services
- Cryptocurrency exchanges
- Any service linked to your Facebook email or phone
👉 Use our Emergency Password Reset Protocol
⚠️ Step 3: Watch for Breach‑Specific Scams
Expect increased:
- SMS phishing messages
- Fake “Facebook Support” calls (Facebook never calls users)
- Friend‑impersonation scams
Best Defense:
- Never click links in unsolicited texts
- Type website URLs manually
- Verify urgent requests by calling contacts directly
Frequently Asked Questions
Was this listed on Have I Been Pwned?
Yes. The Facebook dataset is indexed, but checking email alone is not sufficient because most exposed records involved phone numbers.
Will Facebook compensate victims?
No compensation, credit monitoring, or identity protection was offered because Facebook classified this as data scraping rather than a breach.
Should I delete my Facebook account?
Deleting your account stops future collection but does not remove your data from criminal databases. You should:
- Remove unnecessary profile details
- Lock down privacy settings
- Disconnect Facebook login from other sites
- Use a dedicated email address for Facebook
Should I change my phone number?
Changing numbers can reduce ongoing harassment, but old numbers remain linked to your identity and Carrier protections are still required.
What NOT to Do After This Leak
❌ Do not rely on Facebook’s security checkup alone
❌ Do not assume silence means safety
❌ Do not continue using SMS‑only 2FA without carrier protection
This Breach in Context
The Facebook leak is part of a broader trend of large‑scale social media scraping:
- LinkedIn (700M users)
- Twitter (220M records)
- Instagram (third‑party app exposures)
This is why Facebook ranks among the Top 50 Biggest Data Leaks — not because of passwords, but because phone numbers are the foundation of modern identity fraud.
👉 See where Facebook ranks in our Top 50 Biggest Data Leaks
Conclusion
Facebook data breach 533 million users is not just a historical headline — it is an active risk event that continues to fuel scams, SIM swaps, and account takeovers years later.
You cannot stop Facebook from losing data.
You can stop criminals from using it.
If this leak involved your information — and statistically, it likely did — the best time to act was yesterday. The second‑best time is now.
👉 Verify your exposure
👉 Build complete defenses
Defense is easier than recovery.
📂 Related Breach Intelligence
Don’t stop here. If your data was in this breach, it is likely in these as well. Check your exposure status in our other Deep Dives:
- [The 50 Biggest Data Leaks in History]: See the full ranking of the most dangerous hacks by “Danger Score.”
- [National Public Data Breach (2.9 Billion Records)]: The massive 2024 leak that exposed the Social Security Numbers of nearly every US adult.
- [Equifax Data Breach Guide]: Why the 2017 “Forever Leak” is the reason you must freeze your credit today.
- [AT&T Call Log Disaster]: How hackers stole the phone records of 86 million customers (and what to do now that the settlement is closed).
- [Facebook Data Breach Guide]: How the “Scraping” leak exposed 533 million phone numbers to spammers.
- [Google+ Data Breach Cover-Up]: The twin API failures that forced Google to shut down its social network.