Free Network Security Tools
Monitor, analyze, and protect network infrastructure with free and open source security tools. Browse network monitoring, intrusion detection, firewall, and traffic analysis tools.
Showing 24 of 500 tools
v2ray-core
v2fly/v2ray-core
A platform for building proxies to bypass network restrictions.
sniffnet
GyulyVGC/sniffnet
Comfortably monitor your Internet traffic 🕵️♂️
algo
trailofbits/algo
Set up a personal VPN in the cloud
setup-ipsec-vpn
hwdsl2/setup-ipsec-vpn
Scripts to build your own IPsec VPN server, with IPsec/L2TP, Cisco IPsec and IKEv2
cilium
cilium/cilium
eBPF-based Networking, Security, and Observability
netbird
netbirdio/netbird
Connect your devices into a secure WireGuard®-based overlay network with SSO, MFA and granular access controls.
RustScan
bee-san/RustScan
🤖 The Modern Port Scanner 🤖
bettercap
bettercap/bettercap
The Swiss Army knife for 802.11, BLE, HID, CAN-bus, IPv4 and IPv6 networks reconnaissance and MITM attacks.
brook
txthinking/brook
A cross-platform programmable network tool
amass
owasp-amass/amass
In-depth attack surface mapping and asset discovery
speedtest
librespeed/speedtest
Self-hosted Speed Test for HTML5 and more. Easy setup, examples, configurable, mobile friendly. Supports PHP, Node, Multiple servers, and more
openvpn
OpenVPN/openvpn
OpenVPN is an open source VPN daemon
cloudflared
cloudflare/cloudflared
Cloudflare Tunnel client
nmap
nmap/nmap
Nmap - the Network Mapper. Github mirror of official SVN repository.
scapy
secdev/scapy
Scapy: the Python-based interactive packet manipulation program & library.
netmaker
gravitl/netmaker
Netmaker makes networks with WireGuard. Netmaker automates fast, secure, and distributed virtual networks.
shadowsocks-rust
shadowsocks/shadowsocks-rust
A Rust port of shadowsocks
ESP32Marauder
justcallmekoko/ESP32Marauder
A suite of WiFi/Bluetooth offensive and defensive tools for the ESP32
MyIP
jason5ng32/MyIP
The best IP Toolbox. Easy to check what's your IPs, IP geolocation, check for DNS leaks, examine WebRTC connections, speed test, ping test, MTR test, check website availability, whois search and more! || 🇨🇳 可能是最好用的IP工具箱。轻松检查你的 IP，IP 地理位置，检查DNS泄漏，检查 WebRTC 连接，速度测试，ping 测试，MTR测试，检查网站可用性，查询 Whois 信息等等。
maltrail
stamparm/maltrail
Malicious traffic detection system
wgcf
ViRb3/wgcf
🚤 Cross-platform, unofficial CLI for Cloudflare Warp
airgeddon
v1s1t0r1sh3r3/airgeddon
This is a multi-use bash script for Linux systems to audit wireless networks.
zeek
zeek/zeek
Zeek is a powerful network analysis framework that is much different from the typical IDS you may know.
arkime
arkime/arkime
Arkime is an open source, large scale, full packet capturing, indexing, and database system.
Related Security Domains
Frequently Asked Questions
What is the best free network monitoring tool?
Wireshark is the gold standard for packet analysis and network troubleshooting. For intrusion detection, Snort and Suricata are the leading free options. Zeek (formerly Bro) provides deep network traffic analysis. Nagios and Zabbix offer comprehensive network monitoring with alerting capabilities.
What is the difference between IDS and IPS?
An IDS (Intrusion Detection System) monitors network traffic and alerts on suspicious activity but takes no action. An IPS (Intrusion Prevention System) actively blocks or drops malicious traffic in real time. Snort and Suricata can operate in both modes depending on configuration.
What is the best free firewall for Linux?
iptables and its modern successor nftables are the standard Linux firewall frameworks. UFW (Uncomplicated Firewall) provides a simpler interface for iptables. pfSense and OPNsense are popular open source firewall distributions for dedicated hardware.
How do I detect network intrusions for free?
Deploy Suricata or Snort as your IDS/IPS engine, feed logs into a SIEM like Wazuh or Graylog, and use Zeek for behavioral analysis. This open source stack provides enterprise-grade detection without licensing costs.