When Facebook CEO Mark Zuckerberg's phone number was leaked along with 533 million Facebook users in the biggest data leaks ever, other details of him came to light, surprising many.

Zuckerberg's details such as his name, birth date, location, marriage details, and Facebook user ID led to the revelation that the Facebook CEO uses the Signal app. A security researcher disclosed it posting the details using Zuckerberg's leaked phone number.

Facebook CEO Mark Zuckerberg
Facebook CEO Mark ZuckerbergTwitter

"In another turn of events, Mark Zuckerberg also respects his own privacy, by using a chat app that has end-to-end encryption and isn't owned by @facebook. This is the number associated with his account from the recent Facebook leak," wrote Dave Walker in a tweet and inserted a screenshot of Zuckerberg's leaked phone number stating:"Mark Zuckerberg is on Signal."


Recently, there was a huge exodus of Facebook users to other platforms and WhatsApp rival Signal was among the alternatives that had attracted many with its policy to keep the messaging platform entirely encrypted.

WhatsApp's new terms dicatate that from May 2021, Facebook can access users' chats with business accounts and use them for advertisements.

Earlier, the Facebook data was leaked exposing the phone number linked to every Facebook account including Zuckerberg and other co-founders Dustin Moskovitz and Chris Hughes. It was reportedly leaked due to a vulnerability that was detected in 2019 and Facebook said it was rectified in August 2019. However, the data was still used by cyber criminals, said security experts.

Facebook data leak

Of the 533 million data of Facebook users, 32 million belonged to the US, 11 million to the UK, and six million to India, according to Alon Gal, who first reported the Facebook data breach on Twitter. "All 533,000,000 Facebook records were just leaked for free. This means that if you have a Facebook account, it is extremely likely the phone number used for the account was leaked. I have yet to see Facebook acknowledging this absolute negligence of your data," he said.

Gal, the CTO of cybercrime intelligence firm Hudson Rock, revealed that the Phone number, Facebook ID, Full name, Location, Past Location, Birthdate, Email Address, Account Creation Date, Relationship Status, Bio of the users were among those leaked in the data breach.

How to check whether your Facebook Account is leaked?

Gal has cautioned Facebook users that the cybercriminals will use the information for scamming, hacking, and marketing and suggested users to check online whether their account is compromised or not. The website -- Have I Been Pwned -- or https://haveibeenpwned.com/ is one which is providing info about data leak based on the email address or phone number used to log in to Facebook.