15 free security tools you should try Here are some of the best-known free security tools you can try inside your own network Ellen Messmer January 2, 2013 Network World US Share Twitter Facebook LinkedIn Google Plus There’s a long history of free security software, and here are some of the best-known products you can try inside your own network, if only to discover how vulnerable you are. 1. There’s a long history of free security software, and here are some of the best-known products you can try inside your own network, if only to discover how vulnerable you are. 2. In the desktop anti-virus category, there’s free software from Avira, Avast, and Microsoft Security Essentials. 3. ZoneAlarm, now owned by Check Point, has a free desktop firewall. 4. The Arpwatch bandwidth monitoring tool, developed by Lawrence Berkeley National Lab, is available for free from their site. 5. The Linux-based Network Security Toolkit includes open source security and networking tools for diagnostics and monitoring. 6. PacketSquare is a network protocol testing tool used for testing network devices that include routers, intrusion detection and prevention systems, and switches. 7. Cheops is a network tool mapper for monitoring your network, with the ability to probe hosts to see what scripts are running. 8. Hydra Network Logon Cracker from the Packet Storm website can be used to test for weak passwords. Packet Storm provides many more free tools, such as "IP Phone Scanning Made Easy". 9. SNMP Brute is a tool for brute-force password attacks. 10. Wireshark is an open source packet analyser for deep inspection of hundreds of protocols. 11. Metasploit Framework is the open source penetration testing tool, a free tool available for download from Rapid7, which has also commercialised it. 12. The Ncat utility can read and write data across the network for IPv6 and IPv4, and was created by the nMap Project as a follow-up to the older NetCat mapping tool. 13. NetStumbler is a wireless network discovery tool that provides a way to search for unauthorised wireless LANs. 14. The nMap Security Scanner is an open source utility for network discovery and security auditing. 15. Snort is the open source intrusion detection and prevention system developed by Sourcefire. 16. AirCrack is a suite of tools for 802.11a/b/g/ WEP and WPA cracking.