Open Source Windows Firewall Software
Sort By:
Firewall Software for Windows
View 24 business solutionsBrowse free open source Firewall software and projects for Windows below. Use the toggles on the left to filter open source Firewall software by OS, license, language, programming language, and project status.
-
MongoDB Atlas runs apps anywhereMongoDB Atlas gives you the freedom to build and run modern applications anywhere—across AWS, Azure, and Google Cloud. With global availability in over 115 regions, Atlas lets you deploy close to your users, meet compliance needs, and scale with confidence across any geography.
-
Build Agents and Models on One PlatformGemini Enterprise Agent Platform is Google Cloud's comprehensive platform for developers to build, scale, govern, and optimize agents and models. Choose from Google's most advanced models and third-party models like Anthropic's Claude Model Family.
-
1
simplewall
Simple tool to configure Windows Filtering Platform (WFP)
simplewall is an open-source Windows application that provides a user-friendly firewall control interface powered by Windows Filtering Platform (WFP), enabling users to block or allow outgoing and incoming network connections without diving into complex OS settings or command-line tools. The app presents a clean, intuitive UI where users can define rules based on process names, IP addresses, ports, and protocols, making it possible to restrict apps from accessing the internet or control specific traffic flows with fine granularity. Because simplewall leverages WFP directly, it operates at a low level in the network stack, ensuring reliable enforcement of rules system-wide while remaining lightweight. It also includes optional modes like blocking all inbound or outbound traffic except what’s explicitly allowed, and supports temporary rule application, logging, and diagnostic views to help users understand what traffic is being blocked or permitted. -
2
Privoxy
HTTP proxy to block ads and customize webpages
Privoxy is a non-caching web proxy with advanced filtering capabilities for enhancing privacy, modifying web page data and HTTP headers, controlling access, and removing ads and other obnoxious Internet junk. Privoxy has a flexible configuration and can be customized to suit individual needs and tastes. It has application for both stand-alone systems and multi-user networks. -
3
UPnP PortMapper
Manage port forwardings via UPnP
The UPnP PortMapper can be used to easily manage the port mappings/port forwarding of a UPnP enabled internet gateway/router in the local network. -
4
AgentGuard
AgentGuard is a firewall for AI agents
AgentGuard is a real-time protection layer designed to safeguard AI agents and applications from runaway execution, excessive costs, and unsafe behavior during interaction with large language model APIs. It works by intercepting API calls made by an AI system and continuously monitoring usage, including token consumption and associated costs, allowing developers to enforce strict budget limits. When predefined thresholds are reached, the system can automatically halt execution, trigger alerts, or gracefully terminate processes depending on the configured mode. This makes it particularly valuable in environments where agents operate autonomously and may enter unintended loops or inefficient workflows. The tool integrates directly into existing applications with minimal changes, often requiring only a few lines of code to activate protection. It also supports advanced configurations such as distributed tracking through Redis and webhook notifications for real-time monitoring. -
Custom VMs From 1 to 96 vCPUs With 99.95% UptimeLive migration and automatic failover keep workloads online through maintenance. One free e2-micro VM every month.
-
5
Endian Firewall Community (EFW) is a "turn-key" linux security distribution that makes your system a full featured security appliance with Unified Threat Management (UTM) functionalities. The software has been designed for the best usability: very easy to install, use and manage and still greatly flexible. The feature suite includes stateful packet inspection firewall, application-level proxies for various protocols (HTTP, FTP, POP3, SMTP) with antivirus support, virus and spam-filtering for email traffic (POP and SMTP), content filtering of Web traffic and a "hassle free" VPN solution (based on both OpenVPN and IPsec).
-
6
Advanced Onion Router is a portable client for the OR network and is intended to be an improved alternative for Tor+Vidalia+Privoxy bundle for Windows users. Some of the improvements include UNICODE paths, support for HTTP and HTTPS proxy protocols on the same Socks4/Socks5 port with HTTP header filtering that generates fake identity-dependent headers every time the identity is changed (proxy chains are also supported), support for NTLM proxies, a User Interface that makes Tor's options and actions more accessible, local banlist for forbidden addresses, private identity isolation, a point-and-click process interceptor that can redirect connections from programs that don't support proxies, also giving them fake information about the local system and support for .onion addresses. Also, it can estimate AS paths for all circuits and prevent AS path intersections, it can restrict circuits to be built using only nodes from different countries, can change circuit lengths and more.
-
7
ModSecurity is a web application firewall that can work either embedded or as a reverse proxy. It provides protection from a range of attacks against web applications and allows for HTTP traffic monitoring, logging and real-time analysis.
-
8
PeerGuardian
PeerGuardian - a privacy oriented firewall application
PeerGuardian is a privacy oriented firewall application. It blocks connections to and from hosts specified in huge blocklists (thousands or millions of IP ranges). Its origin seeds in targeting aggressive IPs while you use P2P. PeerGuardian Linux: Not developed actively anymore. Team might still be around. Some unreleased changes on git. Outdated technology. Peerguardian OS X: Not developed anymore. We've lost contact with the OS X developer. PeerGuardian Windows: Not developed anymore. It's highly recommended to use PeerBlock instead, which is a continuation of PeerGuardian's development in Windows, with bug fixes and support for Windows Vista and Windows 7. Collaboration with peerblock.com is welcome! PeerGuardian is an open project. Not only is its source code open for you to read, use, and modify - but the project is open for you to join and contribute in any form (code, documentation, bug reports, web and support). -
9
OPNsense
OPNsense is an open source, easy to use firewall and routing platform
OPNsense is an open source, easy to use and easy to build FreeBSD based firewall and routing platform. OPNsense includes most of the features available in expensive commercial firewalls, and more in many cases. Mission statement of the project: "Give users, developers and businesses a friendly, stable and transparent environment. Make OPNsense the most widely used open source security platform." -
Paessler: Easy to Use With Enterprise Power. Free TrialYou shouldn't have to choose between a monitoring tool that's easy to use and one that's powerful enough for a complex environment. PRTG's low-code interface lets any admin build dashboards, set alerts and monitor devices without scripting, while custom sensors and full API access are there when your team needs deeper control. One platform, no compromise. Download a free 30-day trial now.
-
10
respite vpn - ssh & openvpn injector
Bypass your ISP's firewalls and connect to the internet!
Source: https://github.com/AlizerUncaged/HTTP-Injector respite is a SSH/openVPN client that allows you to connect to the internet with custom injected HTTP Proxy headers. This application requires Java (https://www.java.com/en/download/) and .Net 4.5 (https://www.microsoft.com/en-ph/download/details.aspx?id=42642 .Net 4.5 is already preinstalled in Windows 10). There are many SSH and OpenVPN Server providers in the internet, one is https://www.tcpvpn.com HTTP Proxy responses override (source code): https://github.com/AlizerDoesJava/respite-proxy-override Please rate, any feedback is appreciated. The application and server providers are free. -
11
SafeLine
Serve as a reverse proxy to protect your web services from attacks
SafeLine is a self-hosted WAF(Web Application Firewall) to protect your web apps from attacks and exploits. A web application firewall helps protect web apps by filtering and monitoring HTTP traffic between a web application and the Internet. It typically protects web apps from attacks such as SQL injection, XSS, code injection, os command injection, CRLF injection, LDAP injection, XPath injection, RCE, XXE, SSRF, path traversal, backdoor, brute force, HTTP-flood, bot abuse, among others. By deploying a WAF in front of a web application, a shield is placed between the web application and the Internet. While a proxy server protects a client machine’s identity by using an intermediary, a WAF is a type of reverse-proxy, protecting the server from exposure by having clients pass through the WAF before reaching the server. A WAF protects your web apps by filtering, monitoring, and blocking any malicious HTTP/S traffic traveling to the web application. -
12
360-FAAR Firewall Analysis Audit Repair
360-FAAR Analyze FW1 Cisco Netscreen Policy Offline Using Config/Logs
360-FAAR (Firewall Analysis Audit and Repair) is an offline, command line, firewall policy manipulation tool to filter, compare to logs, merge, translate and output firewall commands for new policies, in Checkpoint dbedit, Cisco ASA or ScreenOS commands, and its one file! Read Policy and Logs for: Checkpoint FW1 (in odumper.csv / logexport format), Netscreen ScreenOS (in get config / syslog format), Cisco ASA (show run / syslog format), 360-FAAR compares firewall policies and uses CIDR and text filters to split rulebases / policies into target sections and identify connectivity for further analysis. 360-FAAR supports, policy to log association, object translation, rulebase reordering and simplification, rule moves and duplicate matching automatically. Allowing you to move rules to where you need them. Build new rulebases from scratch with a single 'any' rule and log files, with the 'res' and 'name' options. Switch into DROPS mode to analyse drop log entries. -
13
CacheGuard Gateway
Free UTM appliance: firewall, VPN, WAF and antivirus in one ISO.
Securing your network should not require an enterprise budget. CacheGuard is a free open-source network security appliance for startups and growing businesses that need serious protection without the complexity. Install CacheGuard-OS on any x86 machine or VM and get a complete security gateway in under an hour. No plug-ins, no compatibility issues. Everything works out of the box. CacheGuard-OS is not an app, it IS the OS. A fully custom network appliance operating system built from scratch over 20 years, now fully open source. One ISO includes: firewall, VPN, web antivirus, URL filtering, SSL inspection, WAF, reverse proxy, load balancer and QoS. Free for any number of users. Optional paid support available. Source code: https://github.com/cacheguard/CacheGuard-OS Website: https://www.cacheguard.com/ -
14
FireHOL
A firewall for humans.
FireHOL is a language (and a program to run it) that builds secure, stateful firewalls from easy-to-understand, human-readable configurations. The configurations stay readable even for very complex setups. FireQOS is a program that sets up traffic shaping from an easy-to-understand and flexible configuration file. Both programs abstract away the differences between IPv4 and IPv6. so you can concentrate on the rules you want. You can apply rules for IPv4 or IPv6, or both, as you need. -
15
BASE is the Basic Analysis and Security Engine. It is based on the code from the Analysis Console for Intrusion Databases (ACID) project. This application provides a web front-end to query and analyze the alerts coming from a SNORT IDS system.
-
16
SonicReader
Sonicwall Configuration File Reader
SonicReader is used to view and save reports of the internals of a Sonicwall Configuration file. This is useful for those people that wish to know the settings within their saved Sonicwall Configs. I have no affiliation with Dell Sonicwall. Please do not contact Dell Sonicwall regarding the use of this program. -
17
HTTP Anti Flood/DoS Security Module
Detect Flooder IPs, Reduce Attack Surface against HTTP Flood Attacks
This module provides attack surface reduction enhancements against the HTTP Flood Attacks at the web application level. Massive crawling/scanning tools, HTTP Flood tools can be detected and blocked by this module via htaccess, firewall or iptables, etc. (like mod_evasive) You can use this module by including "iosec.php" to any PHP file which wants to be protected. You can test module here: http://www.iosec.org/test.php (demo) Watch the Proof of Concept video: http://goo.gl/dSiAL Hakin9 IT Security Magazine Article about IOSEC http://goo.gl/aQM4Di (different format -> http://goo.gl/JKMUPN) IJNSA Article at http://goo.gl/LLxRdX WP Plugin Page http://goo.gl/nF5nD CHANGES v.1.8.2 - Iptables Auto Ban Bash Script Included - Token Access via Implicit Deny - Reverse Proxy Support - reCAPTCHA Support Do you want more features? Check for third party addons http://sf.net/projects/iosecaddons Gökhan Muharremoğlu -
18
Enables tunneling of network connections through restrictive HTTP proxies. Features: Portmapping, SOCKS4, SOCKS5, web-based admin interface, possibility to use standalone server (perl) or hosted server (PHP), optional authorization from LDAP or MySQL
-
19
Coraza
OWASP Coraza WAF is a golang modsecurity compatible firewall library
Coraza is an open-source, enterprise-grade, high-performance Web Application Firewall (WAF) ready to protect your beloved applications. It is written in Go, supports ModSecurity SecLang rulesets and is 100% compatible with the OWASP Core Rule Set. Coraza is a drop-in alternative to replace the soon-to-be abandoned Trustwave ModSecurity Engine and supports industry-standard SecLang rule sets. Coraza runs the OWASP Core Rule Set (CRS) to protect your web applications from a wide range of attacks, including the OWASP Top Ten, with a minimum of false alerts. CRS protects from many common attack categories including: SQL Injection (SQLi), Cross Site Scripting (XSS), PHP & Java Code Injection, HTTPoxy, Shellshock, Scripting/Scanner/Bot Detection & Metadata & Error Leakages. Coraza is a library at its core, with many integrations to deploy on-premise Web Application Firewall instances. -
20
wipfw - IPv4 packet filter and traffic shaper for Windows based on IPFW (FreeBSD firewall).
-
21
Netdeep Secure Firewall
Next Generation Open Source Firewall
Netdeep Secure is a Linux distribution with focus on network security. Is a Next Generation Open Source Firewall, which provides virtually all perimeter security features that your company may need. It offers Web content filters, ensuring better performance of the network, allowing users to use the service efficiently and securely, providing a deep control of the use of the Web access service, blocking access to unwanted websites, Virus, Spam, Applications and intrusion attempts. Its configuration is made entirely by the web interface. -
22
OpenFW UTM Community is a "turn-key" , fork solutions Endian Firewall UTM Community, linux security distribution that makes your system a full featured security appliance with Unified Threat Management (UTM) functionalities. The software has been designed for the best usability: very easy to install, use and manage and still greatly flexible. The feature suite includes stateful packet inspection firewall, application-level proxy HTTP with antivirus support, content filtering of Web traffic and a "hassle free" VPN solution (based on both OpenVPN, IPsec and Wireguard)
-
23
The Nemesis Project is designed to be a command line based, portable human IP stack for UNIX-like and Windows systems. The suite is broken down by protocol, and should allow for useful scripting of injected packets from simple shell scripts.
-
24
-
25
A utility for detecting and resisting BIDIRECTIONAL ARP spoofing. It can anti-spoof for not only the local host, but also other hosts in the same subnet. It is as well a handy helper for gateways which don't work well with ARP.
