Following rumours that the ride-hailing business had been hacked, Uber announced on Thursday that it is looking into a cybersecurity breach.
In a statement posted to Twitter, Uber stated, "We are now responding to a cybersecurity incident."
According to the New York Times, a hacker took over Uber's internal systems after accessing an employee's Slack account and communicating directly with the attacker.
Following Friday's disclosure of the hack, shares of Uber fell 5%.
In a so-called social engineering attack, a hacker gained access to Uber's internal Slack before moving on to other internal systems.
The information could not be independently verified by CNBC.