ADDING BACKDOOR IN HACKED FACEBOOK ACCOUNTS

Here is a way how some hackers retain the hacked facebook accounts even after the target changes the password or the hacker himself returns it to the target.
Many of the facebook users are unaware that there is a alternative way to log in the facebook account by linking a alternate email account to it. Not the default email id which you use regularly to log in by typing the email id and password but a different email id. So when you are logged in this alternate email id and open the facebook website it directly logs in your facebook account without even asking the password. If you did not get the concept here is a example. Imagine that your regular email id is "regular@gmail.com" and you add a alternate email id "alternate@gmail.com" in account setting. Now when you are logged in "alternate@gmail.com"
and open facebook website it redirects you and directly opens your facebook account. So here the is procedure how you can add this alternate email id as a backdoor.

STEP 1) Open your facebook account and go to account settings.

STEP 2) In the settings tab you will see a option "Email" click on "change" and add a new contact email which is to be the backdoor.

STEP 3) Now again in the setting tab you will see a option "Linked accounts" click on "change" and add the type of your alternate email id like google, yahoo etc.

And that's it, your done, now try it. Log of the facebook account, log in the alternate email id and open facebook website and wait, don't stop the loading, after some seconds it will redirect you to the facebook account.

Note:- The targets who got back their hacked accounts should always check if such backdoor was added to their account, if yes then it should be removed quickly.