Facebook admits that hackers exploited a flaw in its View As feature, which lets users see what their profiles look like from other accounts. The vulnerability in the feature left the access tokens of Facebook accounts ripe for the taking. Facebook had originally pegged the number impacted at almost 50 million, after further investigation that number has dwindled down to 30 million. Bad actors accessed private data, including potentially users names and contact details (phone number or email), gender, language, relationship status, religion and hometown, among other things.
Source: https://threatpost.com/facebook-offers-details-on-view-as-breach/138280/