Facebook Security Breach Exposes Accounts of 50 Million Users

SAN FRANCISCO — Facebook, already facing scrutiny over how it handles the private information of its users, said on Friday that an attack on its computer network had exposed the personal information of nearly 50 million users.

The breach, which was discovered this week, was the largest in the company’s 14-year history. The attackers exploited a feature in Facebook’s code to gain access to user accounts and potentially take control of them.

The news could not have come at a worse time for Facebook. It has been buffeted over the last year by scandal, from revelations that a British analytics firm got access to the private information of up to 87 million users to worries that disinformation on Facebook has affected elections and even led to deaths in several countries.

Senior executives have testified several times this year in congressional hearings where some lawmakers suggested that the government will need to step in if the social network is unable to get tighter control of its service. On Friday, regulators, and lawmakers quickly seized on the breach to renew calls for more oversight.

“This is another sobering indicator that Congress needs to step up and take action to protect the privacy and security of social media users,” Senator Mark Warner, a Democrat from Virginia and one of Facebook’s filtertechnik.mobi, said in a statement. “A full investigation should be swiftly conducted and made public so that we can understand more about what happened.”

In the conference call on Friday, Guy Rosen, a vice president of product management at Facebook, declined to say whether the attack could have been coordinated by hackers supported by a nation-state.