What is Kali Linux?

What is Kali Linux?

Kali Linux is a Debian-based Linux operating system designed for penetration testing, computer forensics, and security auditing. Formerly, it was called BackTrack Linux. Mati Aharoni and Devon Kearns from Offensive Security have rewritten it into what it is today. Kali Linux has hundreds of applications and tools that help in various information security tasks, such as security research, penetration testing, wireless security auditing, reverse engineering, social engineering, computer forensics, and more. The first version (v1.0.0) of Kali Linux got released in March 2013. The latest version of Kali Linux is Kali Linux 2022.3. Security professionals can utilize more than 600 penetration testing tools within it. The official website of Kali Linux is link. The popular categories of utility security tools and apps that come under it are:

• Vulnerability analysis
• Information gathering
• Web applications
• Exploitation tools
• Exploitation tools
• Wireless attacks
• Stress testing programs
• Sniffing tools
• Spoofing tools
• Forensics tools
• Password cracking tools
• Maintaining access
• Hardware hacking
• Honeypot-generating tools
• Reverse engineering tools
• Reporting tools

Now, since we have understood what is Kali Linux, it is time to dig into its history.

A Brief History of Kali Linux

Kali Linux was manufactured from years of experience and expertise to help penetration testers & cybersecurity professionals get a platform where they can perform all types of audits, pen-testing, and cybersecurity research. The first Linux project that originated with a security research-oriented motive was Whoppix (White Hat Knoppix) released in 2004. It opened the door for WHAX (White Hat Slax), which is another project bundled with security tools. It ultimately gave birth to the BackTrack. The first three versions of BackTrack run on Slackware. The fourth and fifth versions leveraged Ubuntu. Kali Linux came right after BackTrack in the year 2013. Debian was chosen to be the underlying distribution that acts as a stable engine beneath the hood. Kali Linux got officially released in March 2013. The cybersecurity training organization, Offensive Security, took the pre-existing security-focused Backtrack Linux OS & redeveloped the BackTrack Linux into Kali with Debian as the base. They made it free of cost. They are responsible for updating its versions and the penetration testing apps residing within it.

Role of Kali Linux in Cybersecurity

Now, that we have understood what is Kali Linux, let's jump into its roles. Kali Linux is known to all cybersecurity professionals, penetration testers, and ethical hackers. It is because Kali Linux provides a wide array of tools and apps that can help security professionals perform various cybersecurity tasks. Here are some of the roles of Kali Linux in cybersecurity. * Usually, cybersecurity tools cost a lot and often become time-consuming to find and download. But Kali Linux comes with more than 600 cybersecurity tools that are pre-installed for use. Also, the operating system is free and open-source.

• Cybersecurity professionals can run it live or install it on a virtual machine, raspberry pi, and other systems.
• The tools & apps that come pre-installed with Kali Linux do not concentrate on one aspect of cybersecurity. It covers a broad cybersecurity domain - such as vulnerability analysis, information gathering, web app pen testing, exploitation tools, wireless attack tools, packet sniffing, spoofing, cyber forensics, hardware hacking, reverse engineering, etc.
• Kali Linux helps in network security auditing. Even the network architects use Kali Linux to check the efficiency and security of the network.
• The organization Offensive Security continuously keeps updating the Kali Linux with the latest versions of the security and penetration testing tools.

Features of Kali Linux

Since we are now familiar with what is Kali Linux and its roles, let us understand its features. Kali Linux comes with a broad spectrum of features that helps cybersecurity professionals and penetration testers ease the audit & testing of their systems and networks. The features are:

1. It is open-source & its repository is open for all to see. Since it is open-source, anyone can tweak and rebuild the packages and tools as required.
2. It comes with a wide range of penetration testing tools on different grounds. The Offensive security team excluded those tools from BackTrack Linux that were outdated, obsolete, or not applicable in the present day.
3. Kali Linux supports a wide range of wireless devices. It can also run on a wide variety of hardware that is either USB compatible (to run the operating system live) or support Linux distros as its operating system.
4. Kali Linux has multilingual support. Although it shows English as its default language, the team ensures that Kali supports multiple languages - ensuring users can work in their native language.
5. The developers of Kali Linux very well know that everyone will not agree with the design model nor will they satisfied with the tools and packages that are there in the operating system. Therefore, the team planned to keep it completely customizable so that anyone or any enterprise could evolve it as per their liking.

Getting Started with Kali Linux

There are different ways to install and start using Kali Linux within the system.

Method 1: Using VirtualBox

1. We have to download the Kali Linux operating system. For this, we have to visit link.
2. Once we download the OVA image file from their official website, we have to open the Oracle VirtualBox in our system.
3. Navigate File > Import Appliance > Appliance to Import screen > Select the OVA file from the pop-up window.
4. Click the Open > Next > Import button. During these steps, you might have to set the path as required.
5. Oracle VirtualBox will import the Kali Linux from the OVA file package into the virtual system. It might take some time (5 – 10 minutes).
6. Once Kali Linux gets installed on your system, you can see it in the left window pane of VirtualBox. You can click the Start button from the top to start using Kali Linux.

Method 2: Using Live USB Mode

Another way to start using Kali Linux is through a Pendrive or flash drive. Now, you have to download the ISO image from their official website. Put the flash drive in your USB port and use tools like BalenaEtcher or Rufus. Browse the downloaded ISO file and start flashing. Once the flashing is over, the USB stick can boot a working Kali Linux operating system.

For using Kali Linux, one can install it directly into the hard disk or use both Windows/Mac along with Kali Linux as a dual-boot.

Popular Pentesting Tools of Kali Linux

We are already familiar with the fact that Kali Linux comes with numerous penetration testing tools. Here are some popular penetration testing tools prominent among all cybersecurity professionals.

• Nmap: Nmap, also known as the Network Mapper, is an open-source and robust tool for vulnerability scanning, network discovery, and port scanning. It got released in 1997. Since then, Nmap has preserved its excellence because of the massive developers' community and contributors who help in maintaining & updating the tool. Penetration testers and security professionals use this tool to scan for network vulnerabilities and discover various devices running within their environment. With Nmap, security professionals can also reveal the services that are running & ports the host is leveraging. It can also help security researchers identify and expose a potential security risk. This tool is powerful enough to monitor a single host or large cluster of systems (consisting of hundreds of computers) within the network.

• Metasploit: Metasploit is a Ruby-based open-source penetration testing framework that helps cybersecurity professionals and attackers identify, exploit, and validate vulnerabilities within systems. H.D Moore developed this framework in 2003 as a Perl-based portable network tool. Later in 2007, the framework got rewritten entirely in Ruby. It comes with various tools, libraries, cracking modules, and user interfaces that allow users to configure & manipulate the target system, pairing it with a payload. The massive database of this framework houses hundreds of exploits and multiple payload options that make hacking easy for both penetration testers and cyber criminalizing Metasploit, attackers can gain access, render information gathering, evade detection, and automate various attacks.

• John the Ripper: Among all the penetration testing techniques, password cracking is one of the most prominent. John the Ripper is a password-cracking software & comes as a part of the Kali Linux operating system. It has customizable features and fuses numerous password-cracking methods to serve individual needs. It got released in 1996 for Unix-based systems as a password-cracking tool. Apart from password cracking, it can test password strengths, perform dictionary attacks, brute-force encrypted passwords, etc. This tool is available in both GNU-licensed and proprietary (professional) versions.

• Netcat: Netcat is a network utility tool that comes as a part of Kali Linux. It can establish UDP and TCP connections & it can read and write inbound and outbound data from any open port. The stable version got released on January 2007. Mostly the network administrators use it for various purposes like DNS forwarding and reverse checking, configuring network source address locally, port scanning, source routing, etc. Netcat can also copy files over the network without using the FTP or HTTP server required for data transmission.

• Wireshark: Wireshark is the most popular network packet analyzer & packet capturing tool that captures network data packets to extract the most granular version of the data traversing within the network. By leveraging this tool, security engineers track data packets to filter out specific data as required. Cybercriminals also use it as a sniffing tool to extract unencrypted data. When anyone executes it for analysis in real time, it renders live data as an indicator of what traffic will go across the network. Network administrators also use it for network troubleshooting. Since it can record the various network scenarios at a microscopic level, network administrators find it a suitable tool to identify the root cause of a network or internet issue.