Protecting your Yahoo account
First, if you get an email saying your Yahoo account may have been hacked and to click this link to re-secure your account, it’s bogus. Yahoo’s official, “you’re screwed” emails have the subject line: “Important Security Information for Yahoo Users” and will look like these examples from Yahoo. Anything else is just a phishing scam.
First, you must change your Yahoo account password on Yahoo services such as Yahoo Mail or Flickr. To do this, go to your Yahoo account page. Once there, go to Account Info and click on Account security. Then, on that page, choose Change password. While you’re at it, you should turn on two-step verification.
Make sure you pick a good password. For example, I like random nonsense phrases passwords. Say, “YahooSecurityIsBreaChed!!” Most password crackers aren’t going to get it, and you’ll be less likely to forget it.
If you, as many people do, use the same password for multiple accounts, stop that. You’re just asking to be hacked. If someone breaks into any of your accounts, lazy hackers can try your most common user name or email with that known password on multiple systems. To be safe, you must use a unique password for every site.
Yahoo has another login authentication option called the Yahoo Account Key. With this, instead of entering passwords, every time you login to your Yahoo account, you’ll get a notification on your Android or Apple device. Personally, I find this annoying, but it might work for you.
Finally. Yahoo’s security questions were also cracked… again. If you still have them, after changing your password, click “Disable security questions” on the Account Security page. Then, disable all of them.