Nessus is one of the most popular remote vulnerability assessments trusted by more than 30,000 organizations worldwide. Nessus scans the system and raises an alert if it discovers any vulnerabilities that malicious hackers could use to gain access.

Nessus does not actively prevent attacks, It will check security loopholes present in infrastructure. It provides detailed system security reports which will be very helpful for fixing any vulnerabilities and make the server more secure.

Nessus is available in many different versions, In this tutorial, we will install the free version of Nessus knows as Nessus Essentials which can scan 16 IPS.

Nessus is a cross-platform vulnerability scanner and supports many OS, but in this article, we will show you how to install Nessue Essentials on Centos 8.

Prerequisites

A server running CentOS 8.

A root password is configured on your server.

Getting Started

Before starting the installation of Nessue it is recommended to update your system packages to the latest version. To do so run the following command:

sudo dnf update -y

Install Nessus

sudo rpm -ivh Nessus-8.13.1-es8.x86_64.rpm

<img alt="Install Nessus as RPM package" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/2.png614883d800b4c.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="156" loading="lazy" src="data:image/svg xml,” width=”750″>

Starting Nessus on CentOS 8

Now run the following commands to start the Nessus service, enable that server at startup and check Nessue service status by running the following command:

sudo systemctl start nessusd.service

sudo systemctl enable nessusd.service

sudo systemctl status nessusd.service

<img alt="Start Nessus daemon" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/3.png614883d8154e1.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="257" loading="lazy" src="data:image/svg xml,” width=”750″>

At this time Nessus service running on default port 8834 successfully, Before you start post-installation, you need to open up that port in your firewall. To do so run the following command:

firewall-cmd --zone=public --add-port=8834/tcp --permanent
firewall-cmd --reload

Now go to your browser and enter your server name or IP along with the default port of Nessus.

https://server_name_or_ip:8834/

Select Nessus Essentials and press the continue button.

<img alt="Nessus web UI" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_13-28-09.png614883d82d329.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="428" loading="lazy" src="data:image/svg xml,” width=”750″>

Then press on skip button,

<img alt="Get activation code" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_14-25-31.png614883d842fd6.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="427" loading="lazy" src="data:image/svg xml,” width=”750″>

Now, Register Nessus by entering the activation code which was sent to your register email.

<img alt="Register Nessus" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_14-26-13.png614883d857a78.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="431" loading="lazy" src="data:image/svg xml,” width=”750″>

Next, enter the Username and password you want to set for Nessus login.

<img alt="Create user account" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_14-26-56.png614883d86e03f.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="427" loading="lazy" src="data:image/svg xml,” width=”750″>

At this point, It will take some time for completing the final steps.

<img alt="Initializing Nessus" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_14-27-24.png614883d884f3e.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="427" loading="lazy" src="data:image/svg xml,” width=”750″>

At this point, your Nessus installation completed successfully.

Nessus Management Console:

After successful installation, you will see the login page of Nessus where you will log in with your username and password.

After login, You can see the Nessus Vulnerability scanner’s dashboard as shown below.

<img alt="Nessus Dashboard" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_16-24-29.png614883d89a822.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="424" loading="lazy" src="data:image/svg xml,” width=”750″>

From the dashboard, click on the ‘New Scan’ button on the top left of your Management console, Here, you can see scanning templates, some of the scanning templates are paid.

<img alt="Scan templates" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_16-25-18.png614883d8abf9f.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="428" loading="lazy" src="data:image/svg xml,” width=”750″>

In this tutorial, we are going to do Basic Network Scan

<img alt="Network scan" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_16-43-45.png614883d8bdc40.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="357" loading="lazy" src="data:image/svg xml,” width=”750″>

Here you will be required to define its name and description. After that select the folder and target the host IP address or Network rage.

On the next tab configure the credentials of your remote host,

<img alt="SSH" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_16-54-29.png614883d8cff82.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="405" loading="lazy" src="data:image/svg xml,” width=”750″>

Once the settings are complete, click on the Save button.

Now you run the scan by selecting the play option as shown below.

<img alt="List of past scans" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_16-57-15.png614883d8e99f2.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="280" loading="lazy" src="data:image/svg xml,” width=”750″>

After the scan completed, click on the Vulnerabilities tab to see the list of vulnerabilities found on the remote host.

<img alt="Network scan" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_17-37-45.png614883d908ca7.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="407" loading="lazy" src="data:image/svg xml,” width=”750″>

To get more details on each vulnerability, click on it for detailed information.

<img alt="SSL Security suites" data-ezsrc="https://kirelos.com/wp-content/uploads/2021/09/echo/arcolinux_2021-04-02_17-39-07.png614883d92af2d.jpg" ezimgfmt="rs rscb5 src ng ngcb5" height="392" loading="lazy" src="data:image/svg xml,” width=”750″>

Conclusion

In the above tutorial, you learned how to install and use Nessus Vulnerability Scanner. You can explore Nessus Vulnerability Scanner and check for other scanning templates. You can now scan the remote computer for any vulnerability through Nessus Vulnerability Scanner. Feel free to ask me if you have any questions.