Data of 533 million Facebook users leaked in a hacking forum for free

On April 3, a user has leaked the phone numbers and personal data of 533 million Facebook users in a hacking forum for free online.

Bad news for Facebook, a user in a hacking forum has published the phone numbers and personal data of 533 million Facebook users. The availability of the data was first reported by Alon Gal, CTO of cyber intelligence firm Hudson Rock.

The data of Facebook users from 106 countries are available for free, over 32 million records belonging to users from the US, 11 from the UK, and 6 million users from India. Leaked data includes users’ phone numbers, Facebook IDs, full names, locations, birthdates, bios, and for some accounts the associated email addresses.

“Insider reviewed a sample of the leaked data and verified several records by matching known Facebook users’ phone numbers with the IDs listed in the data set. We also verified 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.” reported the Business Insider website.

The data was amassed by threat actors by exploiting a vulnerability fixed in 2019 that allowed data scraping from the social network.

The leaked data could be exploited by threat actors to carry out a broad range of malicious activities.

The novelty is not represented by the availability of the data online, which was already reported by Alon Gal in January, but its availability for free.

It’s not the first time that data belonging to hundreds of million Facebook users was published online, in December 2019, security researcher Bob Diachenko discovered more than 267 million Facebook user IDs, phone numbers and names in an unsecured database. The huge trove of data is likely the result of an illegal scraping operation or Facebook API abuse by a group of hackers in Vietnam.

In September 2019, another privacy incident involved Facebook, according to TechCruch, phone numbers associated with 419 million accounts of the social networking giant were exposed online.

The data was found by Sanyam Jain, a security researcher and member of the GDI Foundation, who contacted TechCrunch because he was able to contact the owner of the archive. Data were contained in multiple databases stored on an unsecured server exposed online.

If you want to receive the weekly Security Affairs Newsletter for free subscribe here.

Follow me on Twitter: @securityaffairs and Facebook

[adrotate banner=”9″]

[adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, data leak)

[adrotate banner=”5″]

[adrotate banner=”13″]