Book Image

Nmap: Network Exploration and Security Auditing Cookbook - Second Edition

By : Paulino Calderon
Book Image

Nmap: Network Exploration and Security Auditing Cookbook - Second Edition

By: Paulino Calderon

Overview of this book

This is the second edition of ‘Nmap 6: Network Exploration and Security Auditing Cookbook’. A book aimed for anyone who wants to master Nmap and its scripting engine through practical tasks for system administrators and penetration testers. Besides introducing the most powerful features of Nmap and related tools, common security auditing tasks for local and remote networks, web applications, databases, mail servers, Microsoft Windows machines and even ICS SCADA systems are explained step by step with exact commands and argument explanations. The book starts with the basic usage of Nmap and related tools like Ncat, Ncrack, Ndiff and Zenmap. The Nmap Scripting Engine is thoroughly covered through security checks used commonly in real-life scenarios applied for different types of systems. New chapters for Microsoft Windows and ICS SCADA systems were added and every recipe was revised. This edition reflects the latest updates and hottest additions to the Nmap project to date. The book will also introduce you to Lua programming and NSE script development allowing you to extend further the power of Nmap.
Table of Contents (25 chapters)
Title Page
Credits
About the Author
Acknowledgments
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
13
Brute Force Password Auditing Options
17
References and Additional Reading

Brute forcing SMTP passwords


Mail servers often store very sensitive information. It is critical that organizations use strong password policies, so penetration testers need to perform brute force password auditing against them to check for weak passwords.

This recipe will show you how to launch dictionary attacks against SMTP servers with Nmap.

How to do it...

To launch a dictionary attack against an SMTP server with Nmap, enter the following command:

$ nmap -p25 --script smtp-brute <target>

If any valid credentials are found, they will be included in the script output section:

   PORT    STATE SERVICE REASON
   25/tcp  open   stmp   syn-ack
   | smtp-brute:
   |   Accounts
   |     acc0:test - Valid credentials
   |     acc1:test - Valid credentials
   |     acc3:password - Valid credentials
   |     acc4:12345 - Valid credentials
   |   Statistics
   |_    Performed 3190 guesses in 81 seconds, average tps: 39  

How it works...

The NSE script smtp-brute was submitted by Patrik Karlsson....