Personal data of 533 million Facebook users found on hacking forum

Facebook sign at entrance of its campus
(Image credit: Shutterstock)

Facebook was at the center of a data privacy storm over the weekend after a hacker published 533 million users’ details on a low-level hacking forum.

The data was downloadable for free and allowed anyone downloading it to look up a Facebook user's record using their phone number.

The records, representing roughly a fifth of the company's entire user base, contained users' phone numbers, Facebook IDs, full names, previous locations, birth dates, relationship status, and biographies. It also includes some of their email addresses.

Alon Gal, chief technology officer of cyber crime intelligence company Hudson Rock, tweeted the news on Saturday after discovering the data posted for free on a forum. It followed a tweet he posted in January this year, warning that a vulnerability had allowed the database to be created in early 2020. The January tweet warned that the user had created a Telegram bot that would allow anyone to query the database for a low fee, allowing people to find phone numbers linked to many Facebook accounts.

The January tweet showed the data breach contained 32.3 million US Facebook accounts, representing just under 10% of the entire US population.


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According to a statement Facebook sent to Business Insider, the first outlet to report the news, these stolen credentials aren’t new. Facebook said that it stemmed from a vulnerability it patched in 2019. However, once the hacker stole the data from its network, little can the company do to stop it from spreading online.

"Bad actors will certainly use the information for social engineering, scamming, hacking and marketing," Gal said on Twitter.

Security research Troy Hunt added the data to his website over the weekend to allow people to see if their email addresses are part of the breach. At the time of this writing, he hadn’t yet entered the stolen phone numbers and was considering what to do with that information.

This isn’t the first time Facebook has come under fire for privacy and security issues. In 2019, the FTC fined Facebook $5 billion for misleading users over how it shared their data with third parties and for failing to change its privacy practices following a 2011 FTC settlement.

Danny Bradbury

Danny Bradbury has been a print journalist specialising in technology since 1989 and a freelance writer since 1994. He has written for national publications on both sides of the Atlantic and has won awards for his investigative cybersecurity journalism work and his arts and culture writing. 

Danny writes about many different technology issues for audiences ranging from consumers through to software developers and CIOs. He also ghostwrites articles for many C-suite business executives in the technology sector and has worked as a presenter for multiple webinars and podcasts.