Victim of state spying? Facebook will tell you
Facebook will explicitly notify users it believes have been targeted by an attacker suspected of working on behalf of a nation state, the company has announced.
Users whose accounts are targeted or compromised by state-sponsored hackers will now receive a notification upon login, warning them that we believe your Facebook account and your other online accounts may be the target of attacks from state-sponsored actors.
The user is then prompted to turn on Facebooks login approvals, a form of two-factor authorisation which texts a login code to the user when they (or anyone else) tries to access the app using their phone.
The companys chief security officer, Alex Stamos, explains that the warning is necessary because government-sponsored attacks tend to be more advanced and dangerous than others, necessitating active defence on the part of the target. He also emphasised that being the target of such an attack may indicate that other devices have already been compromised. Ideally, people who see this message should take care to rebuild or replace [their computers or mobile devices] if possible.
http://www.theguardian.com/technology/2015/oct/19/facebook-warn-users-state-spying-hackers