Facebook had a security issue recently, and it looks like they've started sending out e-mails to users who they think have been affected. One such e-mail is above (click for the full size), but what's most worrying is not that friends can see your e-mail or number, it's that there's reports of users finding e-mail addresses and numbers associated with their Facebook account that they never added, and this info has been displayed as well.
Another tipster told TechCrunch she had one email address compromised but noted she cannot figure out how the email was even obtained by Facebook as it appears to be for a former work place, is no longer valid and was never directly associated by her with her account — suggesting Facebook is automatically harvesting contact data from other Facebook users and associating it with other accounts.
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