Zuckerberg's phone number was among the leaked data of 533 million Facebook users.
Apart from his contact number, data including his name, location, marriage details, birth date, and Facebook user ID was also leaked, according to an online report.
A security researcher revealed that Zuckerberg uses Signal by posting his leaked phone number which confirmed the Facebook CEO uses Signal app, "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," security expert Dave Walker posted on Twitter with a screenshot of Zuckerberg's leaked phone number which said, "Mark Zuckerberg is on Signal."
