Mike Isaac and Sheera Frankel:

Facebook on Friday said an attack on its computer network led to the exposure of information from nearly 50 million of its users.

The company discovered the breach earlier this week, finding that attackers had exploited a feature in Facebook’s code that allowed them to take over user accounts. Facebook fixed the vulnerability and notified law enforcement officials.

More than 90 million of Facebook’s users were forced to log out of their accounts Friday morning, a common safety measure for compromised accounts.

Facebook said it did not know the origin or identity of the attackers, nor had it fully assessed the scope of the attack. The company is in the beginning stages of its investigation.

Many services use Facebook credentials – unfortunately.

Brian Krebs has much more.