SAN FRANCISCO — Personal information about 57 million Uber customers and drivers was stolen by hackers last October, a breach the company kept hidden for a year and for which its chief security officer was fired this week, according to a published report.

Bloomberg reported Tuesday that the stolen data including names, email addresses and phone numbers of 50 million Uber riders and 7 million drivers.

The drivers’ stolen information also including 600,000 US. drivers' license numbers.

Uber was legally obliged to report the breach to authorities but instead paid the hackers $100,000 to delete the data and keep mum about it, Bloomberg reported.

Uber’s new president Dara Khosrowshahi this week asked for the resignation of its chief security officer Joe Sullivan and also fired Craig Clark, a senior lawyer who reported to Sullivan, Bloomberg reported.

In a statement to its users, Uber said it did not believe they needed to take action. "We have seen no evidence of fraud or misuse tied to the incident. We are monitoring the affected accounts and have flagged them for additional fraud protection," the statement read.

The fine comes as the ride-hailing company continues to be targeted by lawsuits for assault against its contractor drivers and struggles to polish a brand image that has been tarnished by a sexist corporate culture that toppled cofounder and CEO Travis Kalanick.