A Stored Cross Site Scripting (XSS) Vulneraibiilty exists in Sourcecodester Engineers Online Portal in PHP via the (1) Quiz title and (2) quiz description parameters to add_quiz.php. An attacker can leverage this vulnerability in order to run javascript commands on the web server surfers behalf, which can lead to cookie stealing and more.
https://www.sourcecodester.com/php/13115/engineers-online-portal-php.html
https://www.exploit-db.com/exploits/50451
https://github.com/TheHackingRabbi/CVE-2021-42664
http://packetstormsecurity.com/files/164618/Engineers-Online-Portal-1.0-SQL-Injection.html