Cybersecurity Ops with bash

Chapter 1. Command-Line Primer

A computer’s command-line interface gives you an intimate connection with its operating system (OS). Within the operating system lives an astounding amount of functionality that has been honed and perfected over decades of use and development. Sadly, the ability to interact with the OS by using the command line is quickly becoming a lost art. It has been replaced instead by graphical user interfaces (GUIs), which often increase ease of use at the expense of speed and flexibility, and distance the user from the underlying capabilities.

The ability to effectively use the command line is a critical skill for security practitioners and administrators. Many tools of the trade such as Metasploit, Nmap, and Snort require command-line proficiency simply to use them. During penetration testing, your only option may be to use a command-line interface when interacting with a target system, particularly in the early stages of an intrusion.

In order to build a solid foundation, we will begin with an overview of the command line and its components; then we will look at how it can be applied to enhance your cybersecurity capabilities.

The Command Line Defined

Throughout this book, the term command line is used to refer to all of the various non-GUI executables installed with an operating system, along with, and especially, the built-ins, keywords, and scripting capabilities available from the shell—its command-line interface.

To effectively utilize the command ...