Free network security tools you’ll wish you’d known earlier

In today’s rapidly evolving digital landscape, the importance of robust network security cannot be overstated. With cyber threats becoming more sophisticated by the day, protecting your network is crucial for safeguarding sensitive data and ensuring uninterrupted business operations. Fortunately, there are a plethora of free network security tools available that can provide substantial protection without breaking the bank.

In this blog, we’ll delve into some of the most effective and user-friendly free network security tools that you’ll wish you had discovered earlier. From intrusion detection systems to vulnerability scanners, these tools offer a wealth of features to enhance your network’s security posture, ensuring that your data remains safe from prying eyes. Whether you’re a small business owner, a network administrator, or just someone interested in cybersecurity, this guide will help you navigate the world of free network security tools and make informed decisions to protect your digital assets.

Vulnerability scanning platform/Penetration testing
Nessus is one of the popular vulnerability scanning platform for auditors and security analysts. Users can schedule scans across multiple scanners, use wizards to easily and quickly create policies, schedule scans and send results via email. 

OpenVAS – open source vulnerability scanning suite that grew from a fork of the Nessus engine when it went commercial. Manage all aspects of a security vulnerability management system from web based dashboards.

Metasploit Framework – test all aspects of your security with an offensive focus. Primarily a penetration testing tool, Metasploit has modules that not only include exploits but also scanning and auditing.

Network Mapper/Scanner/Analyzer
Nmap is a popular open source tool for network mapping, port-scanning and testing for network vulnerabilities. Nmap now features powerful NSE scripts that can detect vulnerabilities, misconfiguration and security related information around network services.

Wireshark is a free and open source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education.

Nikto – a web server testing tool that has been around for a while. Nikto is great for firing at a web server to find known vulnerable scripts, configuration mistakes and related security problems. It won’t find your XSS and SQL web application bugs, but it does find many things that other tools miss. To get started try the Nikto Tutorial or the online hosted version.

 Intrusion detection system
OSSEC – host based intrusion detection system or HIDS, easy to setup and configure. OSSEC has far reaching benefits for both security and operations staff.

Security Onion – a network security monitoring distribution that can replace expensive commercial grey boxes with blinking lights. Security Onion is easy to setup and configure. With minimal effort you will start to detect security related events on your network. Detect everything from brute force scanning kids to those nasty APT’s.

Bro IDS totes itself as more than an Intrusion Detection System, and it is hard to argue with this statement. The IDS component is powerful, but rather than focusing on signatures as seen in traditional IDS systems. This tool decodes protocols and looks for anomalies within the traffic.

Snort is a real time traffic analysis and packet logging tool. It can be thought of as a traditional IDS, with detection performed by matching signatures. The project is now managed by Cisco who use the technology in its range of SourceFire appliances. An alternative project is the Suricata system that is a fork of the original Snort source.

Other Security Tools
OpenSSH – secure all your traffic between two points by tunnelling insecure protocols through an SSH tunnel. Includes scp providing easy access to copy files securely. Can be used as poor mans VPN for Open Wireless Access points (airports, coffee shops). Tunnel back through your home computer and the traffic is then secured in transit. Access internal network services through SSH tunnels using only one point of access. From Windows, you will probably want to have putty as a client and winscp for copying files. Under Linux just use the command line ssh and scp.

SANS Investigate Forensic Toolkit (SIFT Kit): The SIFT Workstation is a group of free open-source incident response and forensic tools designed to perform detailed digital forensic examinations in a variety of settings. It can match any current incident response and forensic tool suite. SIFT demonstrates that advanced incident response capabilities and deep dive digital forensic techniques to intrusions can be accomplished using cutting-edge open-source tools that are freely available and frequently updated.

VirusTotal: Analyze suspicious files and URLs to detect types of malware including viruses, worms, and trojans.

GRR – Google Rapid Response a tool developed by Google for security incident response. This python agent / server combination allows incident response to be performed against a target system remotely.