Book Image

Securing Network Infrastructure

By : Sairam Jetty, Sagar Rahalkar
Book Image

Securing Network Infrastructure

By: Sairam Jetty, Sagar Rahalkar

Overview of this book

Digitization drives technology today, which is why it’s so important for organizations to design security mechanisms for their network infrastructures. Analyzing vulnerabilities is one of the best ways to secure your network infrastructure. This Learning Path begins by introducing you to the various concepts of network security assessment, workflows, and architectures. You will learn to employ open source tools to perform both active and passive network scanning and use these results to analyze and design a threat model for network security. With a firm understanding of the basics, you will then explore how to use Nessus and Nmap to scan your network for vulnerabilities and open ports and gain back door entry into a network. As you progress through the chapters, you will gain insights into how to carry out various key scanning tasks, including firewall detection, OS detection, and access management to detect vulnerabilities in your network. By the end of this Learning Path, you will be familiar with the tools you need for network scanning and techniques for vulnerability scanning and network protection. This Learning Path includes content from the following Packt books: •Network Scanning Cookbook by Sairam Jetty •Network Vulnerability Assessment by Sagar Rahalkar
Table of Contents (28 chapters)
Title Page
Copyright and Credits
About Packt

How to detect operating system

Nmap uses TCP/IP stack fingerprinting for OS detection.This is done by crafting custom TCP and UDP packets and analyzing their responses. After generating various such probes and comparing the results to the Nmap-os-db database of more than 2,600 known OS fingerprints and provides the OS version. The fingerprint provides details such as the vendor name, OS name, OS generation, device type, and also their Common Platform Enumeration (CPE) representation. Nmap also provides an option for the user to submit the fingerprint obtained if it is not present in the Nmap database of operating signatures:

  •  -O (Enable OS detection): This enables OS detection for an Nmap scan. This flag further has options that can be used in conjunction with it.
  • --osscan-limit: This option will reduce the scan time when a list of hosts is being scanned by skipping the hosts with no ports open for OS detection, thereby providing faster results for live hosts.
  • --osscan-guess; --fuzzy: If Nmap...