Following other technology giants including Facebook, Twitter, and Google, Yahoo has announced that it will begin alerting users it suspects may have been targeted by a state-sponsored attack. The Internet giant made the announcement in a recent blog post. "Yahoo will now notify you if we strongly suspect that your account may have been targeted by a state-sponsored actor," said Bob Lord, Yahoo's Chief Information Security Officer in the post. "We'll provide these specific notifications so that our users can take appropriate measures to protect their accounts and devices in light of these sophisticated attacks." Some of the actions that the company suggests users should take immediately include turning on Account Key or Two-Step Verification, choosing a strong and unique password, reviewing recent activity in account settings, and checking account recovery info as well as mail forwarding and reply-to settings. It's worth stressing that receiving such a notification from Yahoo doesn't necessarily mean that your account has been hacked by a state-sponsored actor, just that the company "strongly suspects" that it may have happened. The company refused to share any details on its detection methods for obvious...
Source: http://www.gsmarena.com/yahoo_will_now_alert_users_about_suspected_statesponsored_hacking_attacks-news-15712.php