Book Image

BackTrack 5 Wireless Penetration Testing Beginner's Guide

By : Vivek Ramachandran
Book Image

BackTrack 5 Wireless Penetration Testing Beginner's Guide

By: Vivek Ramachandran

Overview of this book

Wireless has become ubiquitous in today’s world. The mobility and flexibility provided by it makes our lives more comfortable and productive. But this comes at a cost – Wireless technologies are inherently insecure and can be easily broken. BackTrack is a penetration testing and security auditing distribution that comes with a myriad of wireless networking tools used to simulate network attacks and detect security loopholes. Backtrack 5 Wireless Penetration Testing Beginner’s Guide will take you through the journey of becoming a Wireless hacker. You will learn various wireless testing methodologies taught using live examples, which you will implement throughout this book. The engaging practical sessions very gradually grow in complexity giving you enough time to ramp up before you get to advanced wireless attacks.This book will take you through the basic concepts in Wireless and creating a lab environment for your experiments to the business of different lab sessions in wireless security basics, slowly turn on the heat and move to more complicated scenarios, and finally end your journey by conducting bleeding edge wireless attacks in your lab.There are many interesting and new things that you will learn in this book – War Driving, WLAN packet sniffing, Network Scanning, Circumventing hidden SSIDs and MAC filters, bypassing Shared Authentication, Cracking WEP and WPA/WPA2 encryption, Access Point MAC spoofing, Rogue Devices, Evil Twins, Denial of Service attacks, Viral SSIDs, Honeypot and Hotspot attacks, Caffe Latte WEP Attack, Man-in-the-Middle attacks, Evading Wireless Intrusion Prevention systems and a bunch of other cutting edge wireless attacks.If you were ever curious about what wireless security and hacking was all about, then this book will get you started by providing you with the knowledge and practical know-how to become a wireless hacker.
Table of Contents (18 chapters)
BackTrack 5 Wireless Penetration Testing
About the Author
About the Reviewer


Wireless Networks have become ubiquitous in today's world. Millions of people use them worldwide every day at their homes, offices, and public hotspots to log on to the Internet and do both personal and professional work. Even though wireless makes life incredibly easy and gives us such great mobility, it comes with its risks. In recent times, insecure wireless networks have been exploited to break into companies, banks, and government organizations. The frequency of these attacks has only intensified, as the network administrators are still clueless on how to secure wireless in a robust and foolproof way.

BackTrack 5 Wireless Penetration Testing: Beginner's Guide is aimed at helping the reader understand the insecurities associated with wireless networks, and how to conduct penetration tests to find and plug them. This is an essential read for those who would like to conduct security audits on wireless networks and always wanted a step-by-step practical guide for the same. As every wireless attack explained in this book is immediately followed by a practical demo, the learning is very complete.

We have chosen BackTrack 5 as the platform to test all the wireless attacks in this book. BackTrack, as most of you may already be aware, is the world's most popular penetration testing distribution. It contains hundreds of security and hacking tools, some of which we will use in this course of this book.

What this book covers

Chapter 1, Wireless Lab Setup, introduces dozens of exercises that we will be doing in this book. In order to be able to try them out, the reader will need to set up a wireless lab. This chapter focuses on how to create a wireless testing lab using off the shelf hardware and open source software. We will first look at the hardware requirements which include wireless cards, antennas, access points, and other Wi-Fi-enabled devices, then we will shift our focus to the software requirements which include the operating system, Wi-Fi drivers, and security tools. Finally, we will create a test bed for our experiments and verify different wireless configurations on it.

Chapter 2, WLAN and its Inherent Insecurities, focuses on the inherent design flaws in wireless networks which makes them insecure out-of-the-box. We will begin with a quick recap of the 802.11 WLAN protocols using a network analyzer called Wireshark. This will give us a practical understanding about how these protocols work. Most importantly, we will see how client and access point communication works at the packer level by analyzing Management, Control and Data frames. We will then learn about packet injection and packer sniffing in wireless networks, and look at some tools which enable us to do the same.

Chapter 3, Bypassing WLAN Authentication, talks about how to break a WLAN authentication mechanism! We will go step-by-step and explore how to subvert Open and Shared Key authentications. In course of this, you will learn how to analyze wireless packets and figure out the authentication mechanism of the network. We will also look at how to break into networks with Hidden SSID and MAC Filtering enabled. These are two common mechanisms employed by network administrators to make wireless networks more stealthy and difficult to penetrate, however, these are extremely simple to bypass.

Chapter 4, WLAN Encryption Flaws, discusses one of the most vulnerable parts of the WLAN protocol are the Encryption schemas—WEP, WPA, and WPA2. Over the past decade, hackers have found multiple flaws in these schemas and have written publically available software to break them and decrypt the data. Even though WPA/WPA2 is secure by design, misconfiguring those opens up security vulnerabilities, which can be easily exploited. In this chapter, we will understand the insecurities in each of these encryption schemas and do practical demos on how to break them.

Chapter 5, Attacks on the WLAN Infrastructure, shifts our focus to WLAN infrastructure vulnerabilities. We will look at the vulnerabilities created due to both configuration and design problems. We will do practical demos of attacks such as access point MAC spoofing, bit flipping and replay attacks, rogue access points, fuzzing, and denial of service. This chapter will give the reader a solid understanding of how to do a penetration test of the WLAN infrastructure.

Chapter 6, Attacking the Client, opens your eyes if you have always believed that wireless client security was something you did not have to worry about! Most people exclude the client from their list when they think about WLAN security. This chapter will prove beyond doubt why the client is just as important as the access point when penetrating testing a WLAN network. We will look at how to compromise the security using client side attacks such as mis-association, Caffe Latte, disassociation, ad-hoc connections, fuzzing, honeypots, and a host of others.

Chapter 7, Advanced WLAN Attacks, looks at more advanced attacks as we have already covered most of the basic attacks on both the infrastructure and the client. These attacks typically involve using multiple basic attacks in conjunction to break security in more challenging scenarios. Some of the attacks which we will learn include wireless device fingerprinting, man-in-the-middle over wireless, evading wireless intrusion detection and prevention systems, rogue access point operating using custom protocol, and a couple of others. This chapter presents the absolute bleeding edge in wireless attacks out in the real world.

Chapter 8, Attacking WPA Enterprise and RADIUS, graduates the user to the next level by introducing him to advanced attacks on WPA-Enterprise and the RADIUS server setup. These attacks will come in handy when the reader has to perform a penetration test on a large Enterprise networks which rely on WPA-Enterprise and RADIUS authentication to provide them with security. This is probably as advanced as Wi-Fi attacks can get in the real world.

Chapter 9, Wireless Penetrating Testing Methodology, is where all the learning from the previous chapters comes together, and we will look at how to do a wireless penetration test in a systematic and methodical way. We will learn about the various phases of penetration testing—planning, discovery, attack and reporting, and apply it to wireless penetration testing. We will also understand how to propose recommendations and best practices after a wireless penetration test.

Appendix A, Conclusion and Road Ahead, concludes the book and leaves the user with some pointers for further reading and research.

What you need for this book

To follow and recreate the practical exercises in this book, you will need two laptops with built-in Wi-Fi cards, an Alfa AWUS036H USB wireless Wi-Fi adapter, BackTrack 5, and some other hardware and software. We have detailed this in Chapter 1, Wireless Lab Setup.

As an alternative to the two laptop setup, you could also create a Virtual Machine housing BackTrack 5 and connect the card to it over the USB interface. This will help you get started with using this book much faster, but we would recommend a dedicated machine running BackTrack 5 for actual assessments in the field.

As a prerequisite, readers should be aware of the basics of wireless networks. This includes having prior knowledge about the basics of the 802.11 protocol and client access point communication. Though we will briefly touch upon some of this when we set up the lab, it is expected that the user is already aware of these concepts.

Who this book is for

Though this book is a Beginner's series, it is meant for all levels of users, from amateurs right through to wireless security experts. There is something for everyone. The book starts with simple attacks but then moves on to explain the more complicated ones, and finally discusses bleeding edge attacks and research. As all attacks are explained using practical demonstrations, it is very easy for readers at all levels to quickly try the attack out by themselves. Please note that even though the book highlights the different attacks which can be launched against a wireless network, the real purpose is to educate the user to become a wireless penetration tester. An adept penetration tester would understand all the attacks out there and would be able to demonstrate them with ease, if requested by his client.


In this book, you will find several headings appearing frequently.

To give clear instructions of how to complete a procedure or task, we use:

Time for action – heading

  1. Action 1

  2. Action 2

  3. Action 3

Instructions often need some extra explanation so that they make sense, so they are followed with:

What just happened?

This heading explains the working of tasks or instructions that you have just completed.

You will also find some other learning aids in the book, including:

Pop quiz – heading

These are short multiple choice questions intended to help you test your own understanding.

Have a go hero – heading

These set practical challenges and give you ideas for experimenting with what you have learned.

You will also find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text are shown as follows: "We enabled the interface using the ifconfig command."

Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: "In order to see the data packets for our access point, add the following to the filter (wlan.bssid == 00:21:91:d2:8e:25) && (wlan.fc.type_subtype == 0x20)."


Warnings or important notes appear in a box like this.


Tips and tricks appear like this.

Reader feedback

Feedback from our readers is always welcome. Let us know what you think about this book—what you liked or may have disliked. Reader feedback is important for us to develop titles that you really get the most out of.

To send us general feedback, simply send an e-mail to , and mention the book title through the subject of your message.

If there is a book that you need and would like to see us publish, please send us a note in the SUGGEST A TITLE form on or e-mail .

If there is a topic that you have expertise in and you are interested in either writing or contributing to a book, see our author guide on

Customer support

Now that you are the proud owner of a Packt book, we have a number of things to help you to get the most from your purchase.


Although we have taken every care to ensure the accuracy of our content, mistakes do happen. If you find a mistake in one of our books—maybe a mistake in the text or the code—we would be grateful if you would report this to us. By doing so, you can save other readers from frustration and help us improve subsequent versions of this book. If you find any errata, please report them by visiting, selecting your book, clicking on the errata submission form link, and entering the details of your errata. Once your errata are verified, your submission will be accepted and the errata will be uploaded on our website, or added to any list of existing errata, under the Errata section of that title. Any existing errata can be viewed by selecting your title from


Piracy of copyright material on the internet is an ongoing problem across all media. At Packt, we take the protection of our copyright and licenses very seriously. If you come across any illegal copies of our works, in any form, on the internet, please provide us with the location address or website name immediately so that we can pursue a remedy.

Please contact us at with a link to the suspected pirated material.

We appreciate your help in protecting our authors, and our ability to bring you valuable content.


You can contact us at if you are having a problem with any aspect of the book, and we will do our best to address it.