• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Tech

Facebook data on 533 million users reemerges online for free

By
Alistair Barr
Alistair Barr
,
Kurt Wagner
Kurt Wagner
, and
Bloomberg
Bloomberg
Down Arrow Button Icon
By
Alistair Barr
Alistair Barr
,
Kurt Wagner
Kurt Wagner
, and
Bloomberg
Bloomberg
Down Arrow Button Icon
April 3, 2021, 5:09 PM ET

The personal data of more than half a billion Facebook users reemerged online for free on Saturday, a reminder of the company’s ability to collect mountains of information and its struggles to protect these sensitive assets.

The leak includes personal information on 533 million Facebook users, such as phone numbers, Facebook IDs, full names, locations, birth dates, bios and in some cases email addresses, Business Insider reported.

“This is old data that was previously reported on in 2019,” a Facebook spokesperson wrote in an email statement. “We found and fixed this issue in August 2019.”

At the time, the company addressed a flaw in its technology that allowed the information to leak out. However, once such data escapes from Facebook’s network, the company has limited power to stop it from spreading online.

Alon Gal, chief technology officer of cybercrime intelligence firm Hudson Rock, discovered the data again on Saturday.

Databases, especially if they are large or rare, aren’t often shared widely right away because “the people who hold it will attempt to monetize it for as long as they can,” Gal said in a message on Twitter. “The process sometimes takes years, sometimes days, but eventually all private databases leak if they were sold around.”

https://twitter.com/UnderTheBreach/status/1349671294808285184

Data leaks threaten to undermine Facebook’s business model of gathering a large amount of personal information and using that to sell targeted ads.

The information is available for free on a hacking forum, making it widely accessible to anyone with rudimentary data skills, Business Insider said. The publication verified several records by matching known Facebook users’ phone numbers with the IDs listed, and confirmed other records by testing email addresses from the data set in Facebook’s password reset feature, which can be used to partially reveal a user’s phone number.

About the Authors
By Alistair Barr
See full bioRight Arrow Button Icon
By Kurt Wagner
See full bioRight Arrow Button Icon
By Bloomberg
See full bioRight Arrow Button Icon

Latest in Tech

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Tech

Amazon is still paying Jeff Bezos an $80,000 yearly salary—but $1.6 million for travel and security
Big TechCEO salaries and executive compensation
Amazon is still paying Jeff Bezos an $80,000 yearly salary—but $1.6 million for travel and security
By Marco Quiroz-GutierrezApril 10, 2026
2 hours ago
Kash Patel sits with his two fingers on lips
CybersecurityIran
First they went after medtech, then Kash Patel. Iranian hackers’ next target is likely ‘low-hanging fruit’ in water, energy, and tourism, experts say
By Jacqueline MunisApril 10, 2026
3 hours ago
scott bessent
CybersecurityFederal Reserve
The AI that found 27-year-old vulnerabilities no human ever caught before just forced an emergency meeting with every major Wall Street CEO
By Jake AngeloApril 10, 2026
4 hours ago
Ukraine will have the most important defense industrial base in the free world, former CIA chief predicts
InnovationDefense
Ukraine will have the most important defense industrial base in the free world, former CIA chief predicts
By Jason MaApril 10, 2026
7 hours ago
A hacker in a dark hoodie and wearing a creepy white mask sits at a keyboard in front of multiple computer monitors in a dark, blue-shaded room.
CybersecurityAnthropic
Anthropic is limiting access to its latest AI model, Mythos. The real risks may already be out there
By Beatrice NolanApril 10, 2026
7 hours ago
‘Downward mobility is incredibly radicalizing’: The college bargain is broken. What comes next could reshape America
EconomyColleges and Universities
‘Downward mobility is incredibly radicalizing’: The college bargain is broken. What comes next could reshape America
By Nick LichtenbergApril 10, 2026
9 hours ago

Most Popular

The U.S. government is spending $88 billion a month in interest on national debt—equal to spending on defense and education combined
Economy
The U.S. government is spending $88 billion a month in interest on national debt—equal to spending on defense and education combined
By Fortune EditorsApril 9, 2026
1 day ago
A Meta employee created a dashboard so coworkers can compete to be the company's No. 1 AI token user—and Zuckerberg doesn't even rank in the top 250
AI
A Meta employee created a dashboard so coworkers can compete to be the company's No. 1 AI token user—and Zuckerberg doesn't even rank in the top 250
By Fortune EditorsApril 9, 2026
2 days ago
Mark Cuban admits he made a mistake letting go of the Mavericks: 'I don't regret selling. I regret who I sold to'
Investing
Mark Cuban admits he made a mistake letting go of the Mavericks: 'I don't regret selling. I regret who I sold to'
By Fortune EditorsApril 9, 2026
1 day ago
'I hate working 5 days': Zoom CEO says traditional work schedules are becoming obsolete—and predicts a 3-day workweek by 2031
Success
'I hate working 5 days': Zoom CEO says traditional work schedules are becoming obsolete—and predicts a 3-day workweek by 2031
By Fortune EditorsApril 9, 2026
1 day ago
Schools across America are quietly admitting that screens in classrooms made students worse off and are reversing years of tech-first policies
Innovation
Schools across America are quietly admitting that screens in classrooms made students worse off and are reversing years of tech-first policies
By Fortune EditorsApril 10, 2026
14 hours ago
Gen Z doesn't want your full-time job. They want several part-time roles, and it's reshaping the entire workforce
Success
Gen Z doesn't want your full-time job. They want several part-time roles, and it's reshaping the entire workforce
By Fortune EditorsApril 9, 2026
2 days ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.