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

SQL injection

Interacting with a backend database to retrieve and write data is one of the most critical tasks performed by a web application. Relational databases that store the data in a series of tables are the most common way to accomplish this, and for querying information, Structured Query Language (SQL) is the de facto standard.

In order to allow users to select what information to see or to filter what they can see according to their profiles, the input taken from cookies, input forms, and URL variables is used to build SQL statements that are passed back to the database for processing. As user input is involved in building the SQL statement, the developer of the application needs to validate it carefully before passing it to the backend database. If this validation is not properly done, a malicious user may be able to send SQL queries and commands that will be executed by the database engine instead of being processed as the expected values.

The type of attacks that abuse the trust...