Reverse Engineering Challenge of Linux binary can you solve it | challenge 7

Hello guys solve this Reversing Challenge and check your skills in Software security.

Linux Binary file link : https://dfreaker.blogspot.com/2018/10/blog-post_23.html

please post your secret key in the comment box of this video as soon as you solve this Reversing Challenge.
Winner names will be announced in the next challenge video.

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