Book Image

Nmap 6: Network Exploration and Security Auditing Cookbook

Book Image

Nmap 6: Network Exploration and Security Auditing Cookbook

Overview of this book

Nmap is a well known security tool used by penetration testers and system administrators. The Nmap Scripting Engine (NSE) has added the possibility to perform additional tasks using the collected host information. Tasks like advanced fingerprinting and service discovery, information gathering, and detection of security vulnerabilities."Nmap 6: Network exploration and security auditing cookbook" will help you master Nmap and its scripting engine. You will learn how to use this tool to do a wide variety of practical tasks for pentesting and network monitoring. Finally, after harvesting the power of NSE, you will also learn how to write your own NSE scripts."Nmap 6: Network exploration and security auditing cookbook" is a book full of practical knowledge for every security consultant, administrator or enthusiast looking to master Nmap. The book overviews the most important port scanning and host discovery techniques supported by Nmap. You will learn how to detect mis-configurations in web, mail and database servers and also how to implement your own monitoring system. The book also covers tasks for reporting, scanning numerous hosts, vulnerability detection and exploitation, and its strongest aspect; information gathering.
Table of Contents (18 chapters)
Nmap 6: Network Exploration and Security Auditing Cookbook
Credits
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
References
Index

Forcing DNS resolution


DNS names reveal valuable information very often because system administrators name their hosts according to their functions, such as firewall or mail.domain.com. Nmap, by default, does not perform DNS resolution if a host is offline. By forcing DNS resolution, we can gather extra information about the network even if the host seemed to be offline.

This recipe describes how to force DNS resolution for offline hosts during Nmap scans.

How to do it...

Open your terminal and enter the following command:

# nmap -sS -PS -F -R XX.XXX.XXX.220-230

This command will force DNS resolution for offline hosts in the range XX.XXX.XXX.220-230.

Consider using a list scan, which will also perform DNS resolution, respectively –sL.

Yes, a list scan will do that. What I'm trying to convey here is that you can include DNS information of hosts that are down during a port scan or when running an NSE script.

How it works...

The arguments -sS -PS -F -R tell Nmap to perform a TCP SYN Stealth (-sS)...