Linux Apps Security

6 Must-Have Open-Source Tools to Secure Your Linux Server

Open Source Linux Security Tools
Written by Divine Okoi

Over the years, I have come across many blogs that claim Linux is impenetrable by security attackers too many times to count. While it is true that GNU/Linux operating systems for desktops and servers come with a lot of security checks in place to mitigate attacks, protection is not “enabled by default”.

This is because your cybersecurity ultimately depends on the tools you have employed to sniff out vulnerabilities, viruses, malware, and to prevent malicious attacks.

In today’s article, we turn our attention to system administrators and security enthusiasts who need to ensure the confidentiality of the data on network servers and local setups. What’s even cooler about these apps is that they are open-source and 100% free!

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So without further ado, here is a list of tools that you must have installed on your machine as a security expert or enthusiast. They are listed in alphabetic order.

1. ClamAV – Linux Antivirus Engine

ClamAV is a robust free and open-source anti-malware engine built to scan for malware and viruses on Linux operating systems. It features multi-threaded scanning for detecting security attacks in real-time by using their signatures for reliable identification.

While ClamAV ordinarily requires you to be conversant with the command line which might be a turn-off to first-time security enthusiasts, it comes bundled with the basic features one needs for malware and virus scans.

ClamAV Antivirus Software

ClamAV Antivirus Software

2. Nikto – Linux Web Server Scanner

Nikto is a web server scanner for performing comprehensive tests against web servers. The tests include checking for outdated server versions, checking for version-specific problems, auto-pause at a specified time, host authentication with Basic and NTLM, Mutation techniques to “fish” for content on web servers, presence of multiple index files, etc. Nikto is free and open-source. Documentation is available on the site for Nikto2.

Nikto Linux Web Server Scanner

Nikto Linux Web Server Scanner

3. Nmap – Linux Network Scanner

Nmap is a powerful free and open-source tool for scanning vulnerabilities in a network. With it, network admins can examine active devices in detail as well as discover available hosts, detect security issues in resident systems, and identify open ports.

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Because Nmap comes with Several experts and even organizations rely on it to monitor multiple complex networks with tons of devices and/or subnets and single hosts. With the ability to analyze IP packets and provide technical information on network devices, you can trust Nmap to come in handy every working day.

Nmap Linux Network Scanner

Nmap Linux Network Scanner

4. Rkhunter – Linux Rootkits Scanner

Rkhunter (Rootkit Hunter) is a free, open-source security monitoring and analyzing tool for POSIX compliant systems. It runs in the background to inform you of malicious attacks the moment one runs on your machine.

Use it to protect against rootkits, local exploits, and to hunt backdoors on both servers and desktops.

Rkhunter Linux Rootkit Scanner

Rkhunter Linux Rootkit Scanner

5. Snort – Linux Network Intrusion

Snort is a prominent open-source Intrusion Prevention System (IPS) for Linux and Windows computers. It features a packet sniffer for real-time traffic analysis which allows for network traffic debugging and IPS. As soon as malicious packets or activity are detected, you will get an alert.

Snort can detect security vulnerabilities thanks to its predefined set of rules against which it scans for malicious network activity. It is definitely a must-have and is available for both personal and business purposes.

Snort Linux Network Intrusion

Snort Linux Network Intrusion

6. Wireshark – Linux Packet Analyzer

Wireshark is a free and open-source network protocol analyzer. With it, you can capture and inspect the content of live data packets in real-time – a feature that makes Wireshark the only network monitoring tool you will need if you have the right skillset.

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It is supported by a global community of network specialists, engineers, and developers who update it with several encryption methodologies and patches.

Wireshark is so feature-rich and trusted by several organizations, and security experts that it is probably the only network traffic inspector you need to develop modern security skills.

Wireshark - Linux Network Packet Analyzer

Wireshark – Linux Network Packet Analyzer

So, there you have it, folks! These are the 6 most important tools that you need in order to make sure that your network is secure. Technically, they won’t make your network impenetrable but knowing how to use them is definitely one of the first steps towards ensuring security.

Are there any tools that you think should be on this list? You’re welcome to make your suggestions in the comments section below.


About the author

Divine Okoi

Divine Okoi is a cybersecurity postgrad with a passion for the open-source community. With 700+ articles covering different topics in IT, you can always trust him to inform you about the coolest tech.