Nmap is one of the most used tools and especially known in Linux that serves to carry out port tracking. It's used to assess the security of computer systems, as well as to discover services or servers on a computer networkFor this, Nmap sends defined packets to other computers and analyzes their responses.
Zenmap is the official graphical interface of Nmap, with which we can perform the different types of analysis which we are allowed to do with Nmap. When it comes to port exploration, Zenmap is king.
About Zenmap
This is a multiplatform application (Linux, Windows, Mac OS X, BSD, etc.) free and open source that aims to make Nmap easy to use for beginners while providing advanced features for experienced Nmap users.
Frequently used scans can be saved as profiles so they are easy to run repeatedly.
Analysis results can be saved and viewed later. The results of saved tests can be compared to each other to see how they differ. Recent test results are stored in a database.
Many people in the security industry use it, and as a result, it is easy to install on most available Linux operating systems. The software is generally found in the repositories of the major Linux distributions.
Leaving vulnerable network ports open is dangerous, having such ports open is a great way for unwanted intruders to gain access to your systems. If you are curious about the status of the ports on your Linux PC, or other network devices on the network, they may want to scan open ports and close any that you are not using.
How to install Zenmap on Linux?
As mentioned, the application can be found in most of the repositories of the main Linux distributions.
For those who are users of Debian, Ubuntu or any distribution derived from these, you can open a terminal with Ctrl + Alt + T and run the following command in it to install the application:
sudo apt install zenmap
If you're user of Arch Linux, Manjaro, Antergos or any distribution derived from Arch Linux, you can install the nmap application on the system which includes Zenmap within the package installation.
To install Nmap, just type in the terminal:
sudo pacman -S install nmap
En the special case of those who are Fedora, CentOS, RHEL users or any distribution derived from these, Zenmap as such is not found within its repositories. But instead there is a package that we can install.
Solo we have to install Nmap and the front-end of it, with the following command:
sudo yum install nmap.
sudo yum install nmap-frontend
While for those who are openSUSE users can install Zenmap without complications just run the following command on the terminal:
sudo zypper in zenmap
For the rest of the distributions we can compile the application from its source code, for this we must download it with:
wget https://nmap.org/dist/nmap-7.70.tar.bz2
We unzip the package with:
bzip2 -CD nmap-7.70.tar.bz2 | tar xvf –
We enter the created directory
cd Nmap-7.70
And we compile with:
./configure
make
su root
make install
How to use Zenmap?
Zenmap is a powerful tool. With that, open ports can be scanned on almost any machine as long as the IP address is known.
To start an analysis, Zenmap must run as root, To do this, open a terminal and execute the following command to start the application with root privileges:
sudo zenmap
To start a scan, type the known IP address into the "target" section.
After typing the IP address in, they will have to select the type of operation to use. Port scanning is generally a long process.
To start a quick scan, click on the profile drop-down menu and select the "quick" option.
On the contrary, if they want to carry out a detailed analysis of the ports in a network, they can do it by selecting the option “Intensive scan” in the Profile drop-down menu.
Due to the great popularity of the tool, you can find many tutorials and videos where they explain its use in more depth.