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 (18 chapters)
13
Brute Force Password Auditing Options
17
References and Additional Reading

Discovering hosts with TCP ACK ping scans


Similar to the TCP SYN ping scan, the TCP ACK ping scan is used to determine if a host is responding. It can be used to detect hosts that block SYN packets or ICMP echo requests, but it will most likely be blocked by modern firewalls that track connection states because it sends bogus TCP ACK packets associated with non-existing connections.

The following recipe shows how to perform a TCP ACK ping scan and its related options.

How to do it...

Open your terminal and enter the following command:

# nmap -sn -PA <target>

The result is a list of hosts that responded to the TCP ACK packets sent, therefore, online:

# nmap -sn -PA 192.168.0.1/24
   Nmap scan report for 192.168.0.1 
   Host is up (0.060s latency). 
   Nmap scan report for 192.168.0.60 
   Host is up (0.00014s latency). 
   Nmap done: 256 IP addresses (2 hosts up) scanned in 6.11 seconds 

How it works...

The -sn option tells Nmap to skip the port scan phase and only perform host discovery. And...