Open Source Vulnerability Assessment Tools & Scanners

Computer systems, software, applications, and other network interfaces are vulnerable to various threats. Failure to find these vulnerabilities can lead to the downfall of the company.

Hence, businesses conduct regular vulnerability assessments for their websites and networks to identify existing loopholes and weaknesses.  

The assessment results can help developers and network administrators understand the security issues and implement the necessary defensive measures against the potential threats. 

This article will go more in-depth on what a vulnerability scanner is. We’ll also introduce our top open-source vulnerability scanning tools that are free and adaptable to various operating systems. 

Let’s get started.

What is a Vulnerability Scanner?

As the name suggests, the term vulnerability scanner is assessing the vulnerabilities in a system or application. It automates security auditing and improves your IT security by scanning your website and network for various security risks. 

The scanner can also generate a prioritized list of the vulnerabilities you should patch, describe what type of vulnerability it is, and provide the necessary steps to fix them. Some scanners also do automated patching. 

It’s crucial to patch any vulnerabilities swiftly because they’re at a much higher risk of cyber-attacks. The threats let hackers enter your security system and exploit the vulnerabilities to their advantage, potentially causing an immense loss for your business. 

Vulnerability scanners rely on a database of known vulnerabilities and automatically test for them. Just like installing fail2ban or antivirus software, these scanners play a crucial role in maintaining maximum security for your website. 

Types of Vulnerability Scanners

Vulnerability scanners are classed into four broad categories, which are: 

Data-based vulnerability scanner

In today’s digital world, databases are heavily burdened with storing critical organizational data. Losing such data can not only result in reputational damage but also potential monetary losses. 

Data-based scanners search for vulnerabilities within databases, such as missing patches, weak passwords, and misconfigurations. They also highlight the weaknesses to users in real-time to allow a swift response. 

Network-based vulnerability scanners

Seamless and constant connectivity within the network dramatically increases the risk of data compromise, hence the existence of network-based vulnerability scanners. 

The scanner identifies weaknesses within the network and looks out for possible network security attacks in both wired and wireless systems in real-time. 

Host-based vulnerability scanners

Even though it includes various security measures embedded in its platform, web hosting can still have some weak spots. 

Hence host-based vulnerability scanners can be installed on every host within the system to provide in-depth insight on potential vulnerabilities and damages done by insiders or outsiders who have partial access.

Some examples of host-based vulnerability scanners that we cover here include OpenVAS and Lynis.

Cloud-based vulnerability scanners

The increased dependency on cloud solutions, especially during this new normal remote working style, has also contributed to the tremendous demand for cloud-based vulnerability scanners. 

These scanners primarily scan and detect possible risks to websites and other online assets that a business has. 

Our Top Vulnerability Scanning Tools

There are many vulnerability scanning tools available online. They can be paid, free, or open-sourced. 

When looking for a vulnerability scanner, you should focus on its reliability, industry reputation, unique features, ease of setup and use, and scalability options. 

This article will focus on the open-source tools that provide plenty of features and are free to use. 

Aircrack-NG Open Source Vulnerability Scanner

Aircrack-ng is a highly regarded open-source vulnerability scanner that specializes in detecting wifi and wireless vulnerabilities. Its main benefits include its speed, accuracy, and flexibility, which make it a valuable tool for security professionals.

Some of the key benefits of Aircrack-ng in detecting wifi and wireless vulnerabilities include:

• Ability to detect vulnerabilities in wifi networks and devices
• Support for a wide range of wireless hardware and protocols
• Comprehensive coverage of wireless vulnerabilities, including WEP and WPA-PSK cracking
• User-friendly interface with extensive documentation and tutorials
• Integration with other security tools and frameworks

What makes Aircrack-ng unique is its advanced algorithms and techniques for detecting wireless vulnerabilities. It can detect hidden wireless networks and perform active and passive scanning. Its modular architecture allows for easy customization and integration with other security tools, making it a versatile and valuable asset for security professionals. The tool's specialized focus on wifi and wireless vulnerabilities makes it particularly well-suited for wireless network security testing.

Anchore Open Source Vulnerability Scanner

Anchore is an open-source, Docker container policy compliance and static analysis tool. Upon activation, it automatically performs image scanning, analysis, and evaluation of the container content. The result provides a policy evaluation for each image and determines whether it passes or fails a business’s requirements. 

Anchore will start working by analyzing the contents of the container image to discover hidden vulnerabilities. It will also scan for known vulnerabilities and assure that the image follows the best security standards and best industry practices. Most importantly, Anchore integrates with container registry and CI/CD tools. 

Anchore is an open-source vulnerability scanner that is designed to help organizations identify and manage vulnerabilities in their containerized environments. It is particularly well-suited for use in DevOps and containerized environments, where applications are deployed in containers and need to be continuously monitored for vulnerabilities.

Here are some reasons why you might want to use Anchore:

Vulnerability detection: Anchore can automatically scan container images for known vulnerabilities and provide detailed reports on the vulnerabilities found.

• Image analysis: Anchore provides detailed information on the contents of container images, including software packages and dependencies, which can help you identify potential security risks.
• Policy enforcement: Anchore allows you to define custom policies for container images and enforce these policies to ensure that only trusted and secure images are used in your environment.
• Integration with CI/CD pipelines: Anchore can be integrated into your CI/CD pipelines to automatically scan container images for vulnerabilities before they are deployed, helping you catch vulnerabilities early in the development process.

Overall, Anchore is a powerful tool that can help you identify and manage vulnerabilities in your containerized environments, and ensure that your applications are deployed in a secure and reliable manner.

Arachni Open Source Vulnerability Scanner

Arachni is a highly regarded open-source vulnerability scanner that specializes in detecting web application vulnerabilities. Its main benefits include speed, accuracy, and flexibility, which make it a valuable tool for security professionals.

Some of the key benefits of Arachni in detecting web vulnerabilities include:

• Comprehensive coverage of web vulnerabilities, including SQL injection, cross-site scripting, and directory traversal
• Ability to scan both static and dynamic content
• Customizable scanning options and reports
• Integration with other security tools and frameworks
• User-friendly interface with extensive documentation and tutorials

What makes Arachni unique is its advanced scanning engine, which uses a combination of heuristics and signatures to identify vulnerabilities. Its modular architecture allows for easy customization and integration with other security tools, making it a versatile and valuable asset for security professionals. The tool's specialized focus on web vulnerabilities makes it particularly well-suited for web application security testing.

Burp Suite Free Edition Open Source Vulnerability Scanner

Burp Suite Free Edition is an open-source vulnerability scanner that provides a comprehensive set of tools for web application security testing, including scanning for vulnerabilities, intercepting and modifying HTTP requests, and analyzing responses.

Some of the key benefits of Burp Suite Free Edition include:

• Support for multiple operating systems and platforms
• Powerful scanning capabilities for web applications
• Ability to identify various types of vulnerabilities, including SQL injection and cross-site scripting
• User-friendly interface with extensive documentation and tutorials
• Integration with other security tools and frameworks

What makes Burp Suite Free Edition unique is its extensive set of features and tools, making it a one-stop-shop for web application security testing. Its ability to intercept and modify HTTP requests allows for testing of complex web applications and APIs. Additionally, the tool's open-source nature allows for community contributions and customizations.

Clair Open Source Vulnerability Scanner

Clair is an API-based vulnerability scanner that lets you check any known security vulnerabilities for each open-source container layer. It makes it simple to create a service that can continuously monitor containers and look for security vulnerabilities.

Clair regularly collects vulnerability metadata from various sources, indexes container images, and provides an API where you can retrieve the features found in the picture. It can also alert you whenever the vulnerability metadata is updated, allowing you to find new vulnerabilities from previously scanned images. 

Clair also provides an API that you can use to query vulnerabilities in specific container images. 

Its main benefits include its speed, accuracy, and scalability, which make it a valuable tool for security professionals.

Some of the key benefits of Clair in detecting container vulnerabilities include:

• Comprehensive coverage of container images and their associated vulnerabilities
• Support for a wide range of container image formats and registries
• Easy integration with container orchestration systems like Kubernetes and Docker Swarm
• User-friendly interface with detailed vulnerability reports
• Ability to scan containers in real-time

What makes Clair unique is its focus on containerized environments and its ability to provide detailed vulnerability reports for container images. While it is not specifically designed to detect wifi and wireless vulnerabilities, it is highly effective in identifying vulnerabilities that could potentially be exploited through containerized wifi or wireless attacks.

Lynis Open Source Host Vulnerability Scanner

Lynis is an open source host-based vulnerability scanner that can be used to identify security issues in Linux and UNIX-based systems. It is designed to be lightweight, easy to use, and highly customizable, allowing users to tailor the scanning process to their specific needs.

Some benefits of using Lynis include:

• Comprehensive scanning: Lynis can identify a wide range of vulnerabilities and misconfigurations in a host, including issues with file permissions, system settings, and network services.
• Easy to use: Lynis is designed to be user-friendly, with clear and concise output that highlights potential security issues and provides guidance on how to fix them.
• Customizable: Users can customize Lynis to their specific needs, tailoring the scanning process to focus on specific areas of concern or to exclude certain checks.
• Open source: Lynis is free and open source, meaning that it can be freely used and modified by anyone, and the source code is available for review and audit.

Overall, Lynis can be a valuable tool for organizations looking to improve the security of their Linux and UNIX-based systems, providing a comprehensive and customizable way to identify and remediate vulnerabilities.

Metasploit Open Source Vulnerability Scanner and Framework

Metasploit is a penetration testing framework that can be used to identify and exploit various types of vulnerabilities in computer systems and networks. Some of the vulnerabilities that Metasploit can detect include:

• Remote code execution vulnerabilities
• SQL injection vulnerabilities
• Cross-site scripting (XSS) vulnerabilities
• Directory traversal vulnerabilities
• Buffer overflow vulnerabilities
• Authentication bypass vulnerabilities
• File inclusion vulnerabilities
• Misconfigured services and applications

In addition to detecting vulnerabilities, Metasploit can also simulate attacks and attempt to exploit the identified vulnerabilities. This allows security professionals to test the effectiveness of their security controls and evaluate the potential impact of an actual attack. Metasploit also has a large library of exploit modules and payloads, which makes it a valuable tool for security professionals and ethical hackers.

Nmap Open Source Vulnerability Scanner

Nmap is a popular open-source vulnerability scanner that is widely used in the security community. It allows users to discover hosts and services on a network, identify potential vulnerabilities, and perform various security-related tasks. Its key benefits include the ability to perform rapid and accurate scanning, detect various types of vulnerabilities, and provide detailed information about target systems.

It’s highly regarded in the open-source security community because of its flexibility, portability, and robustness. It supports a wide range of platforms and operating systems, making it a versatile tool for security professionals. Its ability to detect vulnerabilities and provide detailed reports makes it a critical tool for network administrators and security analysts. Additionally, the tool's open-source nature allows for continual development and customization, enabling the security community to stay ahead of emerging threats.

OpenSCAP Open Source Vulnerability Scanner

OpenSCAP is an open-source vulnerability scanner that is highly regarded in the security community. It provides automated compliance checking, vulnerability scanning, and configuration management for enterprise environments. The tool's main benefits include its flexibility, scalability, and the ability to integrate with various security frameworks.

Some of the key benefits of OpenSCAP include:

• Support for multiple operating systems and platforms
• Automated compliance checking with various security standards, including PCI-DSS and CIS benchmarks
• Configuration management capabilities for large-scale environments
• Integration with other security tools and frameworks
• Open-source nature allows for continuous development and customization

What makes OpenSCAP unique is its comprehensive compliance checking capabilities and ability to manage configurations across multiple systems. It can also scan for known vulnerabilities and suggest remediation steps. The tool's modular architecture allows for easy customization and integration with other security tools, making it a versatile and valuable asset for security professionals.

OpenVAS Open Source Vulnerability Scanner

OpenVAS is a comprehensive open-source vulnerability scanner and management system. It’s free, licensed under GNU General Public License (GPL), and supports different operating systems, including multiple Linux distros. 

OpenVAS utilizes an automatically updated community-sourced vulnerability database of over 50,000 known Network Vulnerability Tests. This means it looks through the entire system in great detail and tests authenticated and unauthenticated protocols. 

The vulnerability tests carried out are incredibly detailed, providing an in-depth analysis of how well guarded the computer and servers are. 

OpenVAS can also be operated from an external server, giving you the hacker’s perspective. This lets you identify the exposed services or ports and solve them quickly. 

Some of the key benefits of OpenVAS include:

• Support for multiple operating systems and platforms
• Ability to scan for over 50,000 known vulnerabilities
• Customizable scanning options and reports
• Integration with other security tools and frameworks
• Open-source nature allows for continuous development and improvement

What makes OpenVAS unique is its ability to provide detailed reports on vulnerabilities and suggest remediation steps. It can also scan for configuration issues and check compliance with security standards like CIS benchmarks. The tool's modular architecture allows for easy customization and integration with other security tools, making it a versatile and valuable asset for security professionals.

Trivy Open Source Vulnerability Scanner

Trivy is an open-source vulnerability scanner that detects CVEs in open-source software. It provides a quick explanation of the risk that lets developers decide whether to use the component in their containers and applications. 

While the usual container security protocols use a static image scan to find vulnerabilities, Trivy goes further by seamlessly merging the vulnerability scanning tool into the Integrated Development Environment (IDE). 

With the vast open-source community, many integrations and add-ons support Trivy, such as utilizing Helm chart to install Trivy to a Kubernetes cluster and Prometheus exporter to extract vulnerability metrics. 

Wapiti Open Source Vulnerability Scanner

Wapiti is a highly regarded open-source vulnerability scanner that is designed to identify web application vulnerabilities. Its main benefits include its accuracy, speed, and flexibility, which make it a valuable tool for security professionals.

Some of the key benefits of Wapiti in detecting web vulnerabilities include:

• Comprehensive coverage of web vulnerabilities, including SQL injection, cross-site scripting, and file inclusion vulnerabilities
• Support for both static and dynamic content
• Customizable scanning options and reports
• Integration with other security tools and frameworks
• User-friendly interface with extensive documentation and tutorials

What makes Wapiti unique is its advanced scanning engine, which uses a combination of heuristics and signatures to identify vulnerabilities. Its modular architecture allows for easy customization and integration with other security tools, making it a versatile and valuable asset for security professionals. While Wapiti is not specifically designed to detect wifi and wireless vulnerabilities, it is highly effective in identifying web vulnerabilities that could potentially be exploited through wifi or wireless attacks.

Wireshark Open Source Protocol Analyzer 

Wireshark is a free and open-source network vulnerability scanner trusted and used by many governmental and educational institutions. It looks into network vulnerabilities at a microscopic level, ensuring a high level of security for your business.

It captures all network traffic, including Bluetooth, wireless, ethernet, token ring, and frame relay connections, to name a few. After finishing the scan, Wireshark goes offline to analyze the data gathered. 

Wireshark runs smoothly on various platforms, including Solaris. The generated analysis report can be converted into simple and plain text, allowing users with no technical background to understand it better. 

Some of the key benefits of Wireshark in detecting network vulnerabilities include:

• Ability to capture and analyze network traffic in real-time
• Support for a wide range of protocols, including wifi and wireless protocols
• Customizable filtering and analysis options
• Graphical visualization of network traffic patterns and anomalies
• Extensive documentation and community support

What makes Wireshark unique is its ability to provide detailed analysis of network traffic, making it a valuable tool for identifying potential vulnerabilities and investigating security incidents. While it is not specifically designed to detect wifi and wireless vulnerabilities, its support for wifi and wireless protocols makes it highly effective in analyzing and identifying potential vulnerabilities in these areas.

Here are some reasons why you might want to use Wireshark:

• Network troubleshooting: Wireshark can help you identify issues with your network infrastructure, such as misconfigurations, dropped packets, or network congestion.
• Security analysis: Wireshark allows you to inspect network traffic and detect potential security threats, such as malware infections, phishing attempts, or unauthorized access attempts.
• Protocol analysis: Wireshark supports a wide range of network protocols and can help you understand how these protocols work and how they interact with each other.
• Performance optimization: Wireshark can help you optimize network performance by identifying bottlenecks or other issues that may be impacting network speed and reliability.

Overall, Wireshark is a powerful and versatile tool that can help you gain valuable insights into your network and identify potential vulnerabilities or performance issues.

sqlmap Open Source Vulnerability Scanner

Sqlmap is a penetration testing tool but has the features to detect and evaluate vulnerabilities automatically. It goes beyond simply finding security weaknesses and attempts to exploit them and create a detailed report on the results. 

Sqlmap was developed in Python. Hence it supports any operating system that has a Python interpreter installed. It will automatically recognize password hashes and will exploit SQL injection vulnerabilities using six different methods.

An SQL injection (SQLi) attack is a type of web-based attack that targets databases by inserting malicious code into SQL statements through a web application's input forms or other user input fields.

The goal of an SQL injection attack is to manipulate the database in a way that was not intended by the web application's developers, allowing the attacker to extract sensitive information, modify or delete data, or even take control of the entire system.

SQL injection attacks can occur in a variety of environments, including:

• Web applications that rely on user input, such as search forms or login pages.
• Content management systems (CMS) and e-commerce platforms that allow users to create and edit content or product listings.
• Legacy systems that use outdated database technologies or programming languages.
• Mobile applications that interact with a backend database through APIs.

SQL injection attacks can be prevented through various security measures, such as input validation and parameterized queries. It's important for developers and system administrators to be aware of the potential risks associated with SQL injection attacks and take proactive steps to secure their systems.

The tool has a comprehensive database that supports Oracle, PostgreSQL, MySQL, SQL Server, and Access. 

Honorable Mention: OnSecurity Vulnerability Scanner

Scan by OnSecurity is a vulnerability scanning tool that carries out over 40,000 checks for missing patches, security misconfigurations, default passwords and dangerous passwords. It regularly monitors and scans your internet-facing assets. It identifies vulnerabilities before an attacker has a chance to exploit them. Vulnerability scanning helps not only to identify areas you can improve but also provides an inventory of assets. Plus, the OnSecurity Portal dashboard rates each vulnerability with a CVSS score, helping you to prioritize and understand your risk. OnSecurity will notify you as soon as a finding is discovered, in-portal, via SMS, or Slack so you can take immediate action.

Keep Learning About Vulnerability Scanning Tools

Vulnerability scanning is a critical component in how an organization protects itself from threat actors because it helps identify weaknesses and vulnerabilities in the organization's network, systems, and applications. Without a vulnerability scanning program, an organization may not be aware of potential vulnerabilities that could be exploited by attackers, leading to data breaches, system compromise, and other security incidents.

Open source vulnerability tools like Wireshark, OpenVAS, and Nmap are critical tools for an open-source security practitioner to check for these vulnerabilities because they provide a comprehensive view of the organization's network and systems. These tools allow security practitioners to identify and assess vulnerabilities, including weaknesses in system configurations, out-of-date software versions, and network misconfigurations. They also allow practitioners to prioritize and remediate vulnerabilities quickly, reducing the organization's attack surface.

Using open source vulnerability tools is particularly advantageous because they are free and often have a robust user community that contributes to their development and maintenance. This means that they are continuously updated and refined, making them more effective at detecting and addressing emerging threats. Additionally, open source tools are often more transparent and customizable, allowing security practitioners to adapt them to their specific needs and workflows.