Book Image

Penetration Testing Bootcamp

By : Jason Beltrame
Book Image

Penetration Testing Bootcamp

By: Jason Beltrame

Overview of this book

Penetration Testing Bootcamp delivers practical, learning modules in manageable chunks. Each chapter is delivered in a day, and each day builds your competency in Penetration Testing. This book will begin by taking you through the basics and show you how to set up and maintain the C&C Server. You will also understand how to scan for vulnerabilities and Metasploit, learn how to setup connectivity to a C&C server and maintain that connectivity for your intelligence gathering as well as offsite processing. Using TCPDump filters, you will gain understanding of the sniffing and spoofing traffic. This book will also teach you the importance of clearing up the tracks you leave behind after the penetration test and will show you how to build a report from all the data obtained from the penetration test. In totality, this book will equip you with instructions through rigorous tasks, practical callouts, and assignments to reinforce your understanding of penetration testing.
Table of Contents (17 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback

Checking for DNS recursion with NSE

DNS recursion isn't typically an issue, but if you allow outside hosts to use your internal DNS servers for recursion, you are setting yourself up for potential attacks. DNS amplification attacks can be leveraged using these types of setup, where hackers will use these DNS servers to send spoofed requests to them, and they will respond back to the original host and, if there are a large number of these, a DDOS situation.

To check for DNS recursion, we can use Nmap with the NSE engine. The command is straightforward, as we will do a UDP scan on port 53 and turn on the recursive script with the command nmap -sU -p53 -script=dns-recursion HOST.

In this example, the DNS server is correctly set up as they do not allow DNS recursion:

root@pi-kali:~# nmap -sU -p53 --script=dns-recursion NS.XXX.NET
Starting Nmap 7.40 ( ) at 2017-05-06 18:24 UTC
Nmap scan report for NS.XXX.NET (XXX.XXX.XXX.XXX)
Host is up (0.096s latency).