What is Nessus Scanner? Features, Benefits, and Installation

Nowadays, technology is becoming vast, and humans are mostly relying on it to make life easier. Many organizations are using technology to make their services and products even better. But as we heard “With great powers comes great responsibilities” and here the responsibility being talked about is the protection of every user. While checking the network’s security strength we can’t check every part on our own. Here, Nessus vulnerability scanner comes into the picture. It is like using technology to protect technology. Going for the best Cyber Security courses will aid you in getting familiar with the latest cyber security trends.

What is the Nessus Scanner?

Tenable Nessus Scanner is a vulnerability scanner which is developed by Tenable to perform vulnerability assessment and penetration testing using Common Vulnerability and Exposure architecture. It is a subscription-based product. It was its humble beginning of open-source product which turned into a robust commercial product alter after its usage worldwide.

Nessus Docker

You have the option to utilize a managed Tenable Nessus scanner or Tenable Nessus Professional as a Docker image, allowing for deployment within a container. Tenable offers two base Tenable Nessus images, namely Oracle Linux 8 and Ubuntu. By leveraging environment variables, you can conveniently configure the Tenable Nessus instance and automatically apply desired settings to the image. Furthermore, utilizing operators and variables enables seamless deployment of the Tenable Nessus image, linked either to Tenable Vulnerability Management or Tenable.sc.

Who Would Use a Tool Like Nessus?

As the process of vulnerability assessment is long and it requires a lot of time, energy and resources. So, to overcome this issue we use automated vulnerability scanner and Nessus software is one of the popular one nowadays when it comes to automatic vulnerability scanner, and it is used by wide range of individuals in an organization like as follows:

• Security Professionals: Several people come under security professional category like security analyst, penetration tester, vulnerability management team, etc. Nessus security scanner performs thorough security scan and vulnerability assessment and gives detailed report about it with remediation too.
• IT Administrators: They perform scan on daily basis to find any kind of weakness in the system. IT administrators uses Nessus to monitor and maintain their system, application and network.
• System and Security Administrator: Using Nessus they can identify misconfigurations, vulnerabilities and outdated software that may cause threat to the organization. It enables them to take proactive steps to patch the loop holes (vulnerability) to strengthen the infrastructure’s security.
• Software Developers: Software developers uses Nessus during the testing phase of a software. And by conducting regular scan they can identify any security weakness in their code or configuration. It helps them to know the weakness before the deployment of the software.

Why Nessus?

Many organizations and individuals use Nessus for vulnerability assessment and for finding security weakness. There are multiple features of it which makes it a good choice for an organization and individual.

1. Ease to Use and Automation: It has user-friendly interface and offers many automated scanning capabilities which also helps people have different types of technical expertise level. The tool provides the scanning process in such a way that it reduces the time and effort required to identify and mitigate different vulnerabilities effectively.
2. Vulnerability Detection: It always keeps their database up-to-date with the latest vulnerabilities, which allows them to identify wide ranges of vulnerabilities and misconfigurations. Plus, point is that it not only identifies the vulnerability but gives the security measures to protect. It can also detect emerging threats and make the organizations aware by addressing proactive potential security weaknesses.
3. Integration and Collaboration: It has the capability to integrate itself with other security tools like SIEM systems. This integration helps the organization to enhance their incident response capabilities and overall security architecture.
4. Plugin Architecture and Extensibility: Its plugin environment allows users to use their custom plugins or the ones that are developed by Nessus itself to extend the functionality. This flexibility empowers the users to do the assessment based on their unique environment and requirements which enhances the effectiveness of their security assessment.
5. Reporting and Remediation: After the completion of scanning it gives comprehensive information of the identified vulnerabilities and weakness with severity level, and recommended remediation steps. Now these reports will help the security team to prioritize vulnerabilities accordingly to get maximum efficiency.
6. Industry Recognition and Trust: It has emerged as a prominent player among vulnerability scanning tools, earning its reputation as a trusted and widely adopted solution in the industry. Its consistent performance, precise results, and extensive range of features have garnered the confidence of organizations globally, positioning it as a favored option among security professionals and enterprises alike.
7. Tenable Nessus Pricing: In comparison with tenable Nessus cost other products nessus is much more affordable and gives the performance according to the price. It comes with two variants, the first is Nessus Professional and the second is Nessus Expert. Nessus penetration testing is one of the major features, it is utilized most by the organizations.

How Does NESSUS Works in Cyber Security?

Nessus operates as a powerful cybersecurity tool by performing vulnerability scanning and assessment. Here's an overview of how it works in the realm of cybersecurity:

1. Nessus Vulnerability Management

It plays a crucial role in conducting vulnerability assessments. It scans systems and networks for known vulnerabilities, misconfigurations, and weaknesses. By identifying these vulnerabilities, organizations can proactively address them before malicious actors can exploit them.

2. Risk Prioritization

It assigns severity ratings to identified vulnerabilities, helping security professionals prioritize their efforts. Vulnerabilities with higher severity ratings are typically addressed first, as they pose a greater risk to the system's security. This prioritization allows organizations to allocate their limited resources effectively.

3. Comprehensive Scanning

It offers extensive coverage through its vast plugin database, which includes checks for various operating systems, software applications, network devices, and configurations. It provides a comprehensive view of potential vulnerabilities across a wide range of technologies, ensuring thorough scanning and assessment.

4. Continuous Monitoring

It networks monitor feature which performs scheduled or regular network scans. This approach allows organizations to detect newly emerging vulnerabilities or misconfigurations that may arise due to system changes, software updates, or new threats. Regular scans help maintain an up-to-date understanding of the security posture and promptly address any newly discovered vulnerabilities.

5. Compliance Auditing

It aids in compliance assessments by checking systems against industry-specific security standards and regulations. It helps organizations ensure their systems meet the required security controls and guidelines defined by regulatory bodies. It can generate reports highlighting deviations from compliance standards, facilitating the remediation process.

6. Improved Patch Management

It identifies missing patches and updates in systems, including both operating systems and applications. By highlighting the need for patching, it assists organizations in maintaining a strong patch management process. Timely patching is crucial to mitigate vulnerabilities and reduce the attack surface.

7. Reporting and Documentation

It generates detailed reports that provide insights into identified vulnerabilities, their severity, and recommended remediation steps. These reports serve as valuable documentation for security teams, auditors, and stakeholders. They help communicate the security posture, progress in vulnerability mitigation, and compliance status to relevant parties.

8. Integration with Security Ecosystem

It integrates with other security tools and platforms, such as security information and event management (SIEM) systems, ticketing systems, and configuration management tools. This integration allows for streamlined workflows, automated response actions, and centralized visibility, enhancing the overall security operations.

By leveraging the capabilities of Nessus, organizations can enhance their cybersecurity posture, reduce the attack surface, and mitigate potential vulnerabilities and risks. It provides a comprehensive and proactive approach to vulnerability management, enabling security professionals to stay ahead of evolving threats and protect critical systems and data. It requires continuous education in the latest hacking techniques and tools, which can be achieved through CEH training online.

Installation & Using: What is NESSUS?

As mentioned above tenable Nessus is a subscription-based tool, you first must get a subscription of it according to your preference and usage. When you install Nessus vulnerability scanner it comes with Nessusd executable which is nessusd.exe. Follow the following steps:

Step 1: Obtaining the Nessus Installation Package

First you have to get the installation package of Tenable Nessus from its official website according to your operating system and download the latest version for utmost experience and service. Go to Tenable Nessus’s page by clicking here.

You can download it using curl, docker and for virtual machines too.

Step 2: Install Nessus

Once you have downloaded the installation package, follow the provided instructions to install it on your machine. The installation may vary according to your operating system but the installation package will guide you throughout the installation process. Starting it is one of the easiest tasks, once you install it on your system it will direct you to a localhost webpage with the URL as http://localhost/8834.

Here further configurations for setup will be done.

Step 3: Activation of Nessus

When you start it for the first time, it will give a prompt for the activation of the product. For the activation of the product, you have to create a tenable account and register the product and get the activation code which will activate your product.

You will get the page as above if you go for its professional trial.

Step 4: Configure Nessus

Once activated, you will find a wizard to create a user account. Create a user account.

After account creation it will download and setup plugins.

Then the you will be redirected to the dashboard of Nessus Professional. In case you if you are not able to start the scan wait for some time because compilation of plugins is taking place and after that you can start your work. You can check the progress of plugins compilation at the menu-bar where you can see a loop logo, before “Resource Center” option.

1. Using Nessus (part 1): Running a Scan

There are several Nessus scan types available for different methods of scanning like Host Discovery, network scan, advance scan, malware scan, Credential and Audit patch and many more. Host Discovery is the most common one and the one which is used most of the time at the beginning of the scan. Host Discovery tells the live hosts or any ports of the targeted system.

For the testing purpose we will consider http://testphp.vulnweb.com.

• Basic: Let’s use Basic Network Scan, it is a full system scan. Fill all the required input fields that are asked like name, description, target, etc. There are many more customization available. It also gives us the options to schedule the scan for future.
• Discovery: In the Discovery tab you can select that you want to scan all ports or the common ports.
• Assessment: In assessment tab we can select that what kind of vulnerability want to find means like quick, complex or known vulnerability scan.

Nessus have its own plugin list but if the user wants to use their own plugin, then they can also use their customized plugins from the plugins tab but for that the scan is to be done with Advance Scan option but in our case, we are using Network scan. In advance scan we can customized each any every scan option.

One of the scan methods that is mostly used is nessus advanced scan. It gives the ability to customize or set each policy and parameters by ourself for scanning on specific technologies and getting desired output.

Now save all the setting using save button and launch the scan from the redirected page. After completion of the scanning, we will analyse the report.

2. Using Nessus (part 2): Analyzing the Report

Its reporting is one of the biggest advantages that it provides to its users. Even during scanning, Nessus let us see the current findings. In report you get 3 tabs, Hosts, Vulnerabilities and History. In the hosts tab it shows the proportion of the different severity level vulnerability finding in a single bar. In vulnerability tab it shows the detailed information of the vulnerability or the weakness that had been found. History tabs hold the data of how many times the scans had been performed.

• Hosts Tab: Here we can see the list of the hosts are being listed for scanning with its vulnerability severity bar. From here we can take a small overview of the findings. Pie-charts at the bottom right corner shows the ratio with the severity.
• Vulnerabilities Tab: In vulnerability tab we get the list of all the vulnerabilities and weakness that had been found till now. And by clicking on the it shows the description, effect (severity), solution and the list of the targets that holds the vulnerability.

It gives the risk information too like what’s the severity level. It gives the CVSS (Common Vulnerability Scoring System) too. And for some findings they give reference contents too.

Key Feature of Nessus

• The most significant key feature of Nessus is its comprehensive vulnerability assessment capability. With this feature, it excels at conducting thorough vulnerability assessments across systems, networks, and applications. It goes beyond surface-level scans and actively probes for known vulnerabilities, misconfigurations, default credentials, insecure protocols, and other security weaknesses that could potentially be exploited.
• By leveraging its extensive library of pre-built vulnerability checks and utilizing active scanning techniques, it offers organizations a comprehensive view of their security posture. It identifies and highlights potential points of exploitation, allowing businesses to prioritize and address vulnerabilities before they can be exploited by malicious actors.
• It stands out for its ability to cover a wide range of platforms, including operating systems, databases, nessus web application scanning, and network devices. The library of vulnerability checks is regularly updated to stay current with emerging threats, ensuring that organizations have the latest information to secure their systems effectively.
• Through its comprehensive vulnerability assessments, it empowers organizations to take proactive measures in securing their digital assets. By identifying vulnerabilities, organizations can implement necessary patches, configurations, or security measures to mitigate risks. This feature is especially critical in today's cybersecurity landscape, where threats are constantly evolving, and organizations need robust tools to stay ahead.
• The Comprehensive Vulnerability Assessment feature of Nessus provides organizations with invaluable insights into their security vulnerabilities. By leveraging this capability, businesses can strengthen their defences, protect against potential exploits, and maintain a strong security posture in the face of ever-evolving cybersecurity threats.

What are the Benefits of Nessus?

Some of the major benefits are as follows;

• Scalable Architecture: It is designed to handle large-scale environments, making it suitable for organizations of all sizes. It can efficiently scan thousands of hosts simultaneously, enabling comprehensive vulnerability assessments even in complex and expansive network infrastructures.
• Advanced Scanning Capabilities: It offers advanced scanning options such as credentialed scanning, which allows for authenticated scans to gain deeper insights into the configuration and security of the target systems. This enhances the accuracy and reliability of vulnerability assessments.
• Vulnerability Prioritization: It provides a risk-based approach to vulnerability management. It assigns severity levels to identified vulnerabilities, allowing organizations to prioritize remediation efforts based on the potential impact on the business and the likelihood of exploitation.
• Customization and Flexibility: It allows users to customize scans based on specific requirements. It offers the flexibility to select specific targets, configure scan parameters, and customize reporting formats, enabling organizations to tailor vulnerability assessments to their unique needs.
• Threat Intelligence Integration: It integrates with threat intelligence platforms, enabling organizations to enrich vulnerability data with real-time threat information. This integration enhances the context of vulnerability assessments, allowing security teams to prioritize remediation based on the current threat landscape.
• Remediation Workflow Integration: It facilitates the remediation process by integrating with ticketing and workflow management systems. This enables seamless collaboration between security teams and IT departments, streamlining the vulnerability remediation workflow and ensuring timely resolution of identified issues.
• Regulatory Compliance Reporting: It simplifies compliance reporting by providing built-in templates for various regulatory frameworks, such as PCI DSS, HIPAA, and GDPR. It helps organizations demonstrate adherence to security standards and streamline the compliance reporting process.
• API and Automation Capabilities: It offers an extensive API that allows for integration with other security tools and systems. This enables automation of vulnerability scanning, data retrieval, and reporting, enhancing efficiency and enabling seamless integration with existing security infrastructure.
• Continuous Innovation: It is developed by Tenable, a leading provider of cybersecurity solutions. Tenable consistently invests in research and development, ensuring that Nessus remains at the forefront of vulnerability assessment technology, incorporating the latest advancements and industry best practices.

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Conclusion

Nessus is a powerful and versatile vulnerability assessment tool that helps organizations proactively manage their security risks. With comprehensive coverage, advanced scanning techniques, and compliance auditing capabilities, it provides accurate vulnerability detection. Its scalability, customization options, and integration capabilities make it suitable for organizations of all sizes. By automating processes and offering continuous monitoring, it saves time and resources while ensuring ongoing security vigilance. With a strong user community and continuous innovation, it remains at the forefront of vulnerability assessment technology. Overall, it empowers organizations to strengthen their security, achieve compliance, and protect critical assets.