Personal data of around 53.3 crores Facebook users from 106 countries have allegedly been posted online for free on low-level hacking forums. This has been a major privacy breach from the social media giant.

The exposed data included details like phone numbers, Facebook IDs, full names, locations, birthdates, bios, and even email addresses of some users. Over 3.2 crore accounts in the US, 1.1 crores in the UK, and 60 lakh in India were exposed.

A Facebook spokesperson said that the leaked data was scrapped due to a vulnerability that the company patched in 2019. A vulnerability was discovered in 2019 that allowed phone numbers of millions of users to be scraped from Facebook servers. The social media giant said that the vulnerability was patched in August 2019.

Even though the leaked data is a couple of years old, it could provide valuable information to cybercriminals, said Alon Gal, CTO of cybercrime intelligence firm Hudson Rock who first discovered the leaked data online on Saturday.

"A database of that size containing the private information such as phone numbers of a lot of Facebook's users would certainly lead to bad actors taking advantage of the data to perform social engineering attacks or hacking attempts," said Gal to the news site.

This means that if you have a Facebook account, it is extremely likely the phone number used for the account was leaked.