An online attack that forced Facebook to log out 90 million users last month directly affected 29 million people on the social network, the company said Friday as it released new details about the scope of an incident that has regulators and law enforcement on high alert. Through a series of interrelated bugs in Facebook's programming, unnamed attackers stole the names and contact information of 15 million users, Facebook said. The contact information included a mix of phone numbers and email addresses. An additional 14 million users were affected more deeply, having additional details taken related to their profiles, such as their recent search history, gender, educational background, geolocation data, birth dates, and lists of people and pages they follow.

An online attack that forced Facebook to log out 90 million users last month directly affected 29 million people on the social network, the company said Friday as it released new details about the scope of an incident that has regulators and law enforcement on high alert. Through a series of interrelated bugs in Facebook's programming, unnamed attackers stole the names and contact information of 15 million users, Facebook said. The contact information included a mix of phone numbers and email addresses. An additional 14 million users were affected more deeply, having additional details taken related to their profiles, such as their recent search history, gender, educational background, geolocation data, birth dates, and lists of people and pages they follow.