How To Patch SQLI on Your Website: Bypass Admin

What Will I Learn?

• You will learn how to patch bypass admin.
• You will learn how to use PHP filter on your SQL.
• You will learn how hackers work to bypass your admin login page.
• You will learn malicious syntax in SQL.

Requirements

• You must know the use of PHP language.
• You must know SQL.

Difficulty

• Intermediate

Tutorial Contents

Well Hello people, now I wanna teach you how to patch SQLI on your website. Here I just emphasize the bypass admin bug. but first you must know what is SQLI? SQLI (SQL injection) is a hacking technique whereby an attacker can insert SQL commands via url or form form in the website to run database commands. okay now I want to show you how hackers work to bypass your admin login page.

if you saw above you must to be carefully to make a website, now I will tell you some syntax that is considered dangerous and must be removed from your website by filtering it.

'=' 'or'
or 1=1
or 1=1--
or 1=1#
or 1=1/*
admin' --
admin' #
admin'/*
admin' or '1'='1
admin' or '1'='1'--
admin' or '1'='1'#
admin' or '1'='1'/*
admin'or 1=1 or ''='
admin' or 1=1
admin' or 1=1--
admin' or 1=1#
admin' or 1=1/*
admin') or ('1'='1
admin') or ('1'='1'--
admin') or ('1'='1'#
admin') or ('1'='1'/*
admin') or '1'='1
admin') or '1'='1'--
admin') or '1'='1'#
admin') or '1'='1'/*

How to patch this bug?

here I have a source code that is vulnerable to this bug

<?php
include'connection.php';
if (isset($_POST['login']))
{
    $name=$_POST['name'];
    $password=$_POST['password'];
    $query="SELECT * FROM admin where admin_name='$name' AND admin_password='$password'";
    $rq=mysqli_query($conn,$query);
    if (mysqli_num_rows($rq) > 0) {
        $id=0;
        @session_start();
        $_SESSION['admin_name']=$name;
        $_SESSION['user']=$id;
            echo "<script>
alert('Logged in');
window.location.href='index.php';
</script>";
    }
    else
    {
        echo "<script>
alert('Email or Password is inavlid');
window.location.href='login.php';
</script>"  
    }   
}
?>

you can see on that source without PHP filter, the PHP filter that should be used is addslashes () function. The addslashes () function is a string function to give a slash or slash if there are certain characters in the string. The characters are: Single Quote ('); Double Quote ("); backslash (). You can see again at above where syntax that is considered dangerous using Single Quote ('); Double Quote ("); backslash (), so this function very important to your website right?. We can put addslashes to that source in part

 $name=$_POST['name'];
    $password=$_POST['password'];

and you can add addslashes() function like this

$name=addslashes($_POST['name']);
    $password=addslashes($_POST['password']);

if you already to put addslashes() function Like that I promise your website now don't have that bug again :)

see the picture below I have patched BYPASS ADMIN bug on my website

okay until here i teach you How To Patch SQLI on Your Website: Bypass Admin. Cheerio!

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Posted on Utopian.io - Rewarding Open Source Contributors

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