The company behind popular ride-sharing app Uber has said its database was infiltrated by a third party in 2014, leading to possible theft of information about 50,000 drivers in its network.
In a blog post, the company confirmed in late 2014 it identified a one-time access by an unauthorised third party of an Uber database that contained current and former Uber driver partner names and driver's licence numbers.
"Immediately upon discovery we changed the access protocols for the database, removing the possibility of unauthorised access. We are notifying impacted drivers, but we have not received any reports of actual misuse of information as a result of this incident."
"Our investigation determined the unauthorised access impacted approximately 50,000 drivers across multiple states, which is a small percentage of current and former Uber driver partners."
Uber added that it filed a lawsuit in order to gather information about the hacking and prosecute the responsible third party.
Until date, Uber has not received reports of actual misuse of any information as a result of the hacking incident. However, it is notifying drivers about the incident and recommending monitoring their credit reports for fraudulent transactions.
Uber noted it will provide free identity protection service to drivers for one year.
The hacking attack comes as the company is already suffering from a number of issues with regulators around the world. The US ride-hailing company, which has operations in more than 250 cities across the globe, is facing legal hurdles in South Korea, India and a number of European countries.
The company earlier said it was raising the size of its Series E funding round by $1bn (£650m, €878m) to $2.8bn, amid investors' rising appetite for the ride-sharing app.
Uber is currently the second-biggest tech start-up in terms of valuation, behind Chinese smartphone manufacturer Xiaomi that is valued at $45bn.