Like any operating system, Linux is susceptible to attacks on open ports without additional security settings. Through the ports, access to the system is opened, an experienced intruder of your security can damage your data. To close ports, you can enter commands directly from the console.
Necessary
administrator rights
Instructions
Step 1
Start the Linux console. This can be done by pressing Ctrl + Alt + F [console number] on the keyboard or by calling the console from the menu (if you have a graphical shell installed). In this case, all running programs will continue to work. Enter the login and password of the root user. You will need to be logged in as the primary root user to make such changes to the system. If you do not have the login and password of the main user, then you will not be able to make changes to the network settings.
Step 2
Enter the command to close the port: sudo iptables -I INPUT -p tcp -s 0/0 --dport [port number] -j DROP sudo iptables -I INPUT -p udp -s 0/0 --dport [port number] -j DROP Read the manual for this command to familiarize yourself with all the conditions that can be set. You can specify different ports for this command. However, you need to know exactly which port is responsible for what on the computer, since if you do not know certain things, you can completely disrupt the operation of the operating system, as well as some components.
Step 3
Check if the port is open with the command: sudo iptables -L INPUT And then find your port in the table that appears on the screen.
Step 4
You can also close the port with the firestarter utility by entering the command: sudo apt-get install firestarter
Step 5
In the Linux operating system, all service settings of the system are made through the console - the so-called command line. Check out the Linux console help. There are many articles on this topic on the Internet. Also, do not forget that you need to install antivirus software, despite the fact that this operating system is considered safe, since viruses are generally not written for it.
