Kali Linux Practice Lab:
Vulnerability Assessment for Cybersecurity

April 10, 2023
(updated July 10, 2023)

As companies continue to struggle against cyber attacks, they are increasingly adopting a proactive approach to security through the use of blue and red teams. Blue team activities involve the defense and protection of a system, network, or application while red team activities involve simulated attacks on a system, network, or application in order to identify vulnerabilities and weaknesses. Together, red and blue teams play a critical role in keeping systems and data safe from intrusion.

This series of articles will cover some of the aspects of blue team (defensive) operations. While there are many components of blue team operations, these articles will address 4 key activities of defensive cybersecurity and give you foundational knowledge on the topic. The activities are as follows:

• Network and System Monitoring


• Vulnerability Assessment


• Access Control


• Patch Management

We'll now explore some of the most commonly used Linux commands and tools employed by blue teams for vulnerability assessment.

Vulnerability Assessment

Vulnerability assessment is a key component of cybersecurity. Below is a description of commands and tools commonly utilized for assessing vulnerability.

Defensive Activity:
Identify, classify, and prioritize vulnerabilities in a network and system.

Linux Commands and Tools

There are many commands that can be used for vulnerability assessment in Linux. Here are 20 commands and tools that can be useful in accomplishing the task. Each command has many options and variations. Consult the manual pages to determine which ones work best for your needs.

1. nmap

nmap - scan hosts and ports on a network and identify open services and vulnerabilities.

Displays open services and ports on the given host or hosts.

nmap [authorized_address]

Documentation: nmap.org or man7.org

See also Zenmap Documentation

2. nikto

nikto - web server scanner that identifies known vulnerabilities and misconfigurations.

To scan an SSL-enabled website.

nikto -h -ssl [authorized_address or authorized_host_name]

Documentation

3. OpenVAS

OpenVAS - vulnerability assessment scanner that performs over 50,000 network vulnerability tests.

Documentation

4. Nessus

Nessus - vulnerability scanner that identifies security issues in hosts and web applications.

Documentation

5. Metasploit

Metasploit - penetration testing framework that includes tools for discovering and exploiting vulnerabilities.

Documentation

6. Burp Suite

Burp Suite - web application security testing tool that includes vulnerability scanning features.

Documentation

7. sqlmap

sqlmap - automated tool for detecting and exploiting SQL injection vulnerabilities.

Documentation

8. dirb

dirb - web application directory and file brute-forcing tool that can identify sensitive information or hidden content.

dirb [authorized_website]

Documentation

9. dnsrecon

dnsrecon - DNS reconnaissance tool that can identify subdomains and DNS misconfigurations.

Documentation

10. whois

whois - query WHOIS information to gather information about domain names and IP addresses.

whois [address]

Documentation

11. sslscan

sslscan - scan SSL/TLS certificates for vulnerabilities and configuration issues.

sslscan [authorized.com]

Documentation

12. wireshark

wireshark - network protocol analyzer that can be used to identify security issues and vulnerabilities in network traffic.

Documentation

13. tcpdump

tcpdump - packet capture utility that can be used to analyze network traffic and identify potential vulnerabilities.

tcpdump -D

Documentation

14. netcat

netcat - tool for testing network connections and ports for vulnerabilities and misconfigurations.

Listen on a specified port

nc -l -p [port]

Documentation

15. iptables

iptables - firewall tool that can be used to identify and block potentially malicious traffic.

sudo iptables -L --line-numbers

Documentation

16. psad

psad - intrusion detection tool that can be used to detect suspicious activity on a system.

psad is a service that must be installed (sudo apt install psad) and requires some configuration before starting. For installation, configuration, and service start, see Geeks for Geeks.

Documentation

17. Snort

Snort - intrusion detection and prevention system that can detect and block network attacks.

Documentation

18. OSSEC

OSSEC - host-based intrusion detection system that can detect suspicious activity on a system.

Documentation

19. Lynis

Lynis - security auditing tool that can be used to identify security issues and misconfigurations on a Linux system.

Documentation

20. Nexpose

Nexpose vulnerability scanner is an automated penetration testing system that helps to identify the open ports, applications, and services on each scanned machine.

Documentation

Conclusion

Linux provides a powerful and versatile environment for vulnerability assessment. By utilizing basic Linux commands and tools, you can quickly and effectively identify potential vulnerabilities in your system, network, or application. Whether you are a beginner or an experienced professional, understanding and mastering these basic tools is essential for maintaining the security and integrity of your systems. So, be sure to keep these commands and tools in your arsenal and use them regularly to stay ahead of potential threats.

Frequently Asked Questions (FAQ)

Q1: What is vulnerability testing?

A1: Vulnerability testing, also known as vulnerability assessment, is the process of identifying and evaluating vulnerabilities in computer systems, networks, and applications. It helps organizations understand their security weaknesses and take appropriate measures to mitigate potential risks.

Q2: Why is vulnerability testing important?

A2: Vulnerability testing is crucial for maintaining a secure environment as it helps identify weaknesses that could be exploited by attackers. By proactively assessing vulnerabilities, organizations can take corrective actions to prevent security breaches, data leaks, and unauthorized access.

Q3: What is Kali Linux?

A3: Kali Linux is a powerful open-source penetration testing platform that provides a comprehensive set of tools for conducting various security assessments, including vulnerability testing. It is widely used by cybersecurity professionals and enthusiasts for ethical hacking and security testing purposes.

Q4: How can I set up a Kali Linux practice lab?

A4: Setting up a Kali Linux practice lab involves:

• Downloading the Kali Linux ISO image from the official website.


• Installing Kali Linux on a virtual machine or as a dual-boot system.


• Configuring networking and ensuring connectivity to target systems for testing.


• Installing and updating the required tools and packages.

Q5: What are some essential vulnerability testing tools available in Kali Linux?

A5: Kali Linux offers a wide range of vulnerability testing tools, including:

• OpenVAS: A powerful vulnerability scanner for comprehensive network vulnerability assessments.


• Nikto: A web server scanner that identifies potential vulnerabilities in web applications.


• Nmap: A versatile network mapping and port scanning tool useful for detecting open ports and potential vulnerabilities.


• Burp Suite: A web application security testing framework for identifying and exploiting web application vulnerabilities.


• Metasploit Framework: A robust exploitation framework that helps assess and exploit vulnerabilities in target systems.

Q6: How can I install additional tools in Kali Linux for vulnerability testing?

A6: Kali Linux provides the Advanced Package Tool (APT) package management system. To install additional tools, you can use the apt-get command followed by the name of the tool. For example: sudo apt-get install tool-name.

Q7: How do I perform a vulnerability assessment using Kali Linux?

A7: Performing a vulnerability assessment with Kali Linux involves:

• Identifying the target system or network to assess.


• Conducting a thorough scan using appropriate tools, such as OpenVAS or Nmap, to identify vulnerabilities.


• Analyzing the scan results and prioritizing vulnerabilities based on severity.


• Generating comprehensive reports that highlight the identified vulnerabilities and recommended remediation steps.

Q8: Is vulnerability testing legal?

A8: Yes, vulnerability testing is legal when performed with proper authorization and consent. It is crucial to obtain permission from the system owner before conducting any vulnerability testing to ensure compliance with legal and ethical standards.

Q9: Can I use Kali Linux for personal vulnerability testing?

A9: Yes, you can use Kali Linux for personal vulnerability testing and learning purposes. However, it is important to adhere to ethical guidelines and conduct testing only on systems you have permission to assess.

Q10: Are there any certifications available for vulnerability testing?

A10: Yes, there are various certifications available for vulnerability testing, such as Certified Ethical Hacker (CEH), Offensive Security Certified Professional (OSCP), and Certified Information Systems Security Professional (CISSP).