A data breach on the Quora website gave hackers access to the data of 100 million users.

According to CNN, “The compromised information includes users’ names, email addresses and encrypted passwords as well as data from social networks like Facebook (FB) and Twitter (TWTR) if people chose to link them to their Quora accounts.”

Quora CEO Adam D’Angelo said in a corporate blog that the firm had discovered unauthorized access by a malicious third party. The question-and-answer site is working to contain the incident and an investigation is in process. Said D’Angelo, “We believe we’ve identified the root cause and taken steps to address the issue, although our investigation is ongoing and we’ll continue to make security improvements.”

As part of its effort to address the situation, Quora has been logging users out of its site, invalidating passwords, and notifying the users impacted.

CNN reports, “The hackers also obtained details about users’ activity on Quora, such as questions, answers, upvotes and downvotes. But anonymously written questions and answers were not affected by the breach.”

Get the full story at CNN.