User Registration & Login and User Management System 2.1 - Login Bypass SQL Injection

# Exploit Title: User Registration & Login and User Management System 2.1 - Login Bypass SQL Injection 
# Date: 2020–11–14
# Exploit Author: Mayur Parmar(th3cyb3rc0p)
# Vendor Homepage: https://phpgurukul.com
# Software Link: https://phpgurukul.com/user-registration-login-and-user-management-system-with-admin-panel/
# Version: 2.1
# Tested on POPOs(Linux)

SQL Injection:
SQL injection is a web security vulnerability that allows an attacker to alter the SQL queries made to the database. This can be used to retrieve some sensitive information, like database structure, tables, columns, and their underlying data.

Attack Vector:
An attacker can gain admin panel access using malicious sql injection quiries.

Steps to reproduce:
1. Open admin login page using following URl:
-> http://localhost/loginsystem/admin/

2. Now put below Payload in both the fields( User ID & Password)
Payload: ' or '1'='1

3. Server accepted our payload and we bypassed admin panel without any credentials, 

IMPACT:
if any attacker can gain admin panel access than they can Update & Delete Userdata 

Suggested Mitigation/Remediation Actions
Parameterized queries should be used to separate the command and data portions of the intended query to the database. These queries prevent an attacker from tampering with the query logic and extending a concatenated database query string. Code reviews should be conducted to identify any additional areas were the application or other applications in the organization are vulnerable to this attack.
Additionally, input validation should be enforced on the server side in order to ensure that only expected data is sent in queries. Where possible security specific libraries should be used in order to provide an additional layer of protection.