This is big. Hackers who have access to your primary email account can get into almost anything they want. If you use Yahoo – make sure you change your password ASAP. And while you are at it – you should enabled 2 Factor Authentication AND the login page shield (which shows a picture you'll recognize on EVERY login for Yahoo. Makes it easy to know when you're at a fake one trying to grab your info)

Timeline Photos
Head's up Yahoo email users: Usernames and passwords of some customers have been stolen and used to gather personal information