In this section, we will learn about the various features available in Nmap and Nessus. This helps the user to fully understand the tools and their capabilities before using them.

The default screen on the Nessus web interface, Scans, is shown in the following screenshot; this is where you can see all the scans that you have scheduled/performed. In the top right, you can toggle between the Scans and Settings pages. Next, we will look into the scans interface:

The left pane of the Nessus default screen displays multiple tabs classified into folders and resources. The folders are basically different views of scans present on the server. For example, selecting the Trash...

Nessus is a vulnerability scanner developed by Tenable Network Security. It scans hosts and subnets for network-level and service-level vulnerabilities. Nessus is available free of charge with restricted features for non-business users. It consists of two main components: NessusD (Nessus Daemon), and a client application that can be hosted on the same machine. Nessus Daemon is responsible for performing the scan and delivering the result to the client application, providing these results in various formats. Tenable also develops incremental updates and detection mechanisms, called plugins, which can be downloaded and updated regularly. It also provides additional probing functionality of known vulnerabilities; for example, if an FTP port is found to be open, Nessus will automatically try to log in using the anonymous user. Nessus has both a command...

Nmap is a free and open source network scanning and audit tool available at https://Nmap.org/. This tool is one of the most important components of a network-level security audit, as it allows the user to monitor or observe the network-level posture of a host by providing data about open ports and services running on these ports. The Nmap tool also allows interaction with these services and the running of various scripts using Nmap Script Engine (NSE). The following command is the syntax to perform TCP syn full port scanning on the host 127.0.0.1:

Nmap -sS -p1-65535 127.0.0.1

We will be looking into recipes for the usage of the Nmap tool in further chapters.

Nmap is available in...

Nessus can be updated either manually, or by scheduling automatic updates. The software update option can be found as a part of the Settings menu. This can be used to schedule daily, weekly, or monthly updates for Nessus software or even just the plugins. By default, Nessus uses its cloud server to download and install the updates, but you can also configure a custom server to download these updates.

You can update Nessus while connected to the internet or offline. If you want a hassle-free update or a quick one, you can ensure that the system is connected to the internet.

However, in order to update Nessus offline, you will have to download the update package from the Nessus website.

The most straightforward way to update Nmap is to download the latest available version of the software and manually install the package.

Download the latest stable version from https://Nmap.org/download.html/, making sure to choose the right version for the current operating system in use.

Perform the following steps:

1. Right-click on the downloaded file and select Run as administrator. This is required to ensure that the tool has all the privileges to be installed properly on your machine.
2. After this, you will be shown an open...

Removing the Nessus software is similar to removing Nmap. Once done, the port on which the service was running will be free and you will no longer be able to access the web interface.

The steps to remove Nessus vary from platform to platform. Before uninstalling Nessus, you may wish to back up all your policies and scan data by exporting them in the required format; for example, NessusDB.

Follow these steps to uninstall Nessus on Windows:

1. Navigate to the Control Panel on a Windows machine
2. Select Uninstall or change a program...

The uninstallation process of Nmap is pretty straightforward on both Windows and Linux. This will remove all the dependencies and libraries that have been installed by Nmap.

Follow these steps to uninstall Nmap on Windows:

1. Navigate to the Control Panel of the Windows machine
2. Select Uninstall or change a program
3. Locate and select the Nmap package in the list of software installed
4. Click Uninstall

This will uninstall the Nmap software and its data from any Windows machine.

In Linux-based distributions you can simply delete...