Book Image

Mastering Modern Web Penetration Testing

By : Prakhar Prasad, Rafay Baloch
Book Image

Mastering Modern Web Penetration Testing

By: Prakhar Prasad, Rafay Baloch

Overview of this book

Web penetration testing is a growing, fast-moving, and absolutely critical field in information security. This book executes modern web application attacks and utilises cutting-edge hacking techniques with an enhanced knowledge of web application security. We will cover web hacking techniques so you can explore the attack vectors during penetration tests. The book encompasses the latest technologies such as OAuth 2.0, Web API testing methodologies and XML vectors used by hackers. Some lesser discussed attack vectors such as RPO (relative path overwrite), DOM clobbering, PHP Object Injection and etc. has been covered in this book. We'll explain various old school techniques in depth such as XSS, CSRF, SQL Injection through the ever-dependable SQLMap and reconnaissance. Websites nowadays provide APIs to allow integration with third party applications, thereby exposing a lot of attack surface, we cover testing of these APIs using real-life examples. This pragmatic guide will be a great benefit and will help you prepare fully secure applications.
Table of Contents (18 chapters)
Mastering Modern Web Penetration Testing
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Bypassing upload protections


Most of the time, there will be some sort of protection mechanisms to prevent malicious file uploads.

For example, server-side script uploads, such as PHP or JSP, are often not allowed. We shall go through different protections that developers often use and can be bypassed.

Case-sensitive blacklist extension check bypass

Developers, sometimes, add a blacklist for certain file extensions, which is considered harmful. Sometimes, they forget whether their extension verification is case-insensitive, which means a blacklist for the PHP file extension .php should be denied, and so should .php, .PhP, .pHP, and other variants, developers often check for the lower cases of the extension and disregard the variants (case insensitive checks).

Consider the following PHP file upload code, which tries to deny different types of PHP file extensions (.php, .php3, and so on):

<?php
   if(isset($_FILES['image'])){
      $filename = $_FILES['image']['name'];
      $tmp=$_FILES['image...