Kali Linux

Kali Linux is an open-source, Debian-based Linux distribution that is geared towards various information security tasks.

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Kali Linux is an open-source, Debian-based Linux distribution that is geared towards various information security tasks, such as Penetration Testing, Security Research, Computer Forensics and Reverse Engineering. It is maintained and funded by Offensive Security Ltd, a provider of world-class information security training and penetration testing services. Kali Linux was developed by Mati Aharoni and Devon Kearns of Offensive Security through the rewrite of BackTrack, their previous forensics Linux distribution.

Named after the Hindu goddess of time, creation, destruction and power, Kali Linux is a powerful tool in the right hands. It is packed with hundreds of security testing tools, making it a must-have arsenal for security researchers. However, it is also a double-edged sword. In the wrong hands, Kali Linux can be used to facilitate malicious activities. Therefore, it is important to use Kali Linux ethically and responsibly.

Installation and configuration

Installing Kali Linux is a straightforward process, similar to installing other Linux distributions. However, it is recommended to install it on a system that is not used for other purposes, as its tools can be dangerous if misused. The installation process involves downloading the ISO image from the official Kali Linux website, writing it to a USB drive or DVD, and booting the system from it. The installer provides a graphical interface that guides the user through the installation process.

After installation, it is important to configure Kali Linux for optimal use. This involves updating the system, installing necessary software, and configuring network settings. It is also recommended to change the default password for the root user, as it is a common target for attackers. Additionally, users should familiarize themselves with the Linux command line, as many of Kali Linux's tools require command line usage.

System requirements

Kali Linux has modest system requirements compared to modern desktop operating systems. It requires a minimum of 20GB of hard disk space, 1GB of RAM, and a 1GHz processor. However, for optimal performance, it is recommended to have at least 40GB of hard disk space, 2GB of RAM, and a 2GHz processor. Additionally, Kali Linux requires a network interface card with driver support for monitor mode, which is necessary for certain types of network security testing.

It is also possible to run Kali Linux on a virtual machine, which allows it to be used alongside other operating systems. This is a popular option for security researchers, as it allows them to use Kali Linux's tools without affecting their main operating system. However, running Kali Linux on a virtual machine has some limitations, such as reduced performance and limited hardware access.

Tools included in Kali Linux

Kali Linux comes pre-installed with a wide range of security testing tools. These tools are organized into categories based on their purpose, such as Information Gathering, Vulnerability Analysis, Web Applications, Password Attacks, Wireless Attacks, Exploitation Tools, Sniffing & Spoofing, Post Exploitation, and Forensics.

Some of the most popular tools included in Kali Linux are Nmap, Wireshark, Metasploit Framework, Burp Suite, Aircrack-ng, and Hydra. These tools are used by security professionals worldwide to test the security of networks and systems. However, it is important to note that these tools should be used responsibly and ethically, as misuse can lead to legal consequences.


Nmap, which stands for Network Mapper, is a free and open-source tool used for network discovery and security auditing. It uses raw IP packets to determine what hosts are available on the network, what services those hosts are offering, what operating systems they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics. It is a powerful tool that can be used to identify vulnerable systems and find potential attack vectors.

However, Nmap is not just a single tool. It is a suite of tools that includes a flexible scripting engine, a network packet generation and response analysis tool, and a host of other utilities. It also has a comprehensive documentation that provides detailed information on how to use each of its features.


Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education. Wireshark lets the user put network interface controllers that support promiscuous mode into that mode, in order to see all traffic visible on that interface, not just traffic addressed to one of the interface's configured addresses and broadcast/multicast traffic.

But Wireshark can also read captured packet files from a wide range of other network analyzers. Furthermore, many protocol dissectors exist to allow it to be used to analyze the traffic of many popular protocols, making it a powerful tool for network analysis.

Using Kali Linux ethically

As mentioned earlier, Kali Linux is a powerful tool that can be used for both good and bad. It is important to use Kali Linux ethically and responsibly. This means using it to improve the security of your own systems, or systems you have been given explicit permission to test. It does not mean using it to break into systems without permission, steal data, or cause harm.

Many countries have laws against unauthorized access to computer systems, and misuse of Kali Linux can lead to legal consequences. Therefore, before using Kali Linux, it is important to understand the ethical and legal implications. It is also recommended to obtain relevant certifications, such as the Certified Ethical Hacker (CEH) certification, which provide a solid foundation in ethical hacking principles and practices.


Kali Linux is a powerful tool for security testing and research. It comes pre-installed with hundreds of security testing tools, making it a must-have arsenal for security researchers. However, it is also a double-edged sword that can be used for malicious activities if misused. Therefore, it is important to use Kali Linux ethically and responsibly.

Whether you are a seasoned security professional, a hobbyist, or a student interested in learning about cybersecurity, Kali Linux can be a valuable tool. However, it is not a magic bullet that will make you a security expert overnight. It requires a solid understanding of networking, programming, and security principles to use effectively. But with time, practice, and patience, Kali Linux can help you take your security skills to the next level.

This post has been updated on 17-11-2023 by Sofie Meyer.

Author Sofie Meyer

About the author

Sofie Meyer is a copywriter and phishing aficionado here at Moxso. She has a master´s degree in Danish and a great interest in cybercrime, which resulted in a master thesis project on phishing.

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