Book Image

Web Penetration Testing with Kali Linux - Third Edition

By : Gilberto Najera-Gutierrez, Juned Ahmed Ansari
Book Image

Web Penetration Testing with Kali Linux - Third Edition

By: Gilberto Najera-Gutierrez, Juned Ahmed Ansari

Overview of this book

Web Penetration Testing with Kali Linux - Third Edition shows you how to set up a lab, helps you understand the nature and mechanics of attacking websites, and explains classical attacks in great depth. This edition is heavily updated for the latest Kali Linux changes and the most recent attacks. Kali Linux shines when it comes to client-side attacks and fuzzing in particular. From the start of the book, you'll be given a thorough grounding in the concepts of hacking and penetration testing, and you'll see the tools used in Kali Linux that relate to web application hacking. You'll gain a deep understanding of classicalSQL, command-injection flaws, and the many ways to exploit these flaws. Web penetration testing also needs a general overview of client-side attacks, which is rounded out by a long discussion of scripting and input validation flaws. There is also an important chapter on cryptographic implementation flaws, where we discuss the most recent problems with cryptographic layers in the networking stack. The importance of these attacks cannot be overstated, and defending against them is relevant to most internet users and, of course, penetration testers. At the end of the book, you'll use an automated technique called fuzzing to identify flaws in a web application. Finally, you'll gain an understanding of web application vulnerabilities and the ways they can be exploited using the tools in Kali Linux.
Table of Contents (19 chapters)
Title Page
Copyright and Credits
Packt Upsell

Authentication schemes in web applications

Before getting into the specific penetration testing concepts, let's review how authentication is done in modern web applications.

Platform authentication

When using platform authentication, users send their credentials in every request's header, using the Authorization variable. Even when they have to submit their credentials only once, the browser or the system stores them and uses them when required.

There are several different types of platform authentication. The most common ones are discussed in the following subsections.


With this type of platform authentication, the username and password are sent attached to the Authorization header and encoded using base64. This means that anybody who sees the request's header is able to decode the credentials to cleartext, as base64 encoding is not a cryptographic format.

The following screenshots show how login information is sent in base64 and how it can be decoded:

You can use Burp Suite's Decoder to...