Best Free Web Application Firewalls (WAF) of 2025

CacheGuard product line is based on a core product called CacheGuard-OS. Once installed on a bare metal or virtual machine, CacheGuard-OS transforms that machine into a powerful network appliance . The resulted appliance can then be implemented as different types of Gateways to Secure & Optimize your network. See below a brief description of all CacheGuard appliances. - Web Gateway: gain control over the Web traffic in your organization & filter unwanted Web traffic in your organization. - UTM (Unified Threat Management) : secure your networks against all kind of threats coming from the internet with a Firewall, an Antivirus at the Gateway, a VPN server and a Filtering proxy. - WAF (Web Application Firewall): block malicious requests on your critical Web applications and protect your business. The WAF integrates OWASP rules with the possibility to design your own custom rules. In addition, an IP reputation based filtering allows you to block IPs listed in real time blacklists. - WAN Optimizer : prioritize your critical network traffic, save your precious bandwidth and get High Availability for your internet access through multiple ISP.

Cloudflare is the foundation of your infrastructure, applications, teams, and software. Cloudflare protects and ensures the reliability and security of your external-facing resources like websites, APIs, applications, and other web services. It protects your internal resources, such as behind-the firewall applications, teams, devices, and devices. It is also your platform to develop globally scalable applications. Your website, APIs, applications, and other channels are key to doing business with customers and suppliers. It is essential that these resources are reliable, secure, and performant as the world shifts online. Cloudflare for Infrastructure provides a complete solution that enables this for everything connected to the Internet. Your internal teams can rely on behind-the-firewall apps and devices to support their work. Remote work is increasing rapidly and is putting a strain on many organizations' VPNs and other hardware solutions.

SKUDONET provides IT leaders with a cost effective platform that focuses on simplicity and flexibility. It ensures high performance of IT services and security. Effortlessly enhance the security and continuity of your applications with an open-source ADC that enables you to reduce costs and achieve maximum flexibility in your IT infrastructure.

Haltdos ensures the 100% high availability of your website/web services by providing intelligent Web Application Firewall and application DDoS mitigation, Bot Protection, SSL offloading, Load Balancing solution over the public and private cloud that monitors, detects, and automatically mitigates a wide range of cyber-attacks including OWASP top 10 and Zero-day attacks, without requiring any human intervention.

Meet the Industry’s Context-Aware API Security Platform Traceable identifies all of your APIs, and evaluates your API risk posture, stops API attacks that lead to incidents such as data exfiltration, and provides analytics for threat hunting and forensic research. With our solution, you can confidently discover, manage and secure all of your APIs, quickly deploy, and easily scale to meet the ongoing needs of your organization.

SafeLine is one of the most popular WAF solutions globally, serving thousands of paid users and hundreds of thousands of active users daily. Utilizing a cutting-edge machine learning engine, it delivers nearly flawless detection rates and minimal false positives by deeply analyzing HTTP traffic semantics. The platform provides comprehensive bot mitigation features such as CAPTCHA challenges and adaptive protections against malicious crawlers. It also defends against large-scale HTTP Flood DDoS attacks by intelligently managing traffic flows and enforcing access controls. SafeLine’s unified identity management supports seamless integration across various cloud and on-premises environments. With an easy-to-use, wizard-driven interface and modular design, organizations can deploy and maintain enterprise-grade protection effortlessly. Pricing transparency ensures users understand exactly what they pay for, with options suited for personal use up to large-scale deployments. SafeLine’s open-source roots foster community-driven improvements, continuously enhancing its capabilities.

We offer the most user-friendly technology without sacrificing performance or features. We back it up with exceptional support and care delivered under a fair, cost-effective pricing model Our technology is used by small startups with big ideas, small budgets, and global enterprises. We love them all! Easy to use Load balancing, WAF, GSLB and SSO/Pre-Authentication. It is also the only true ADP Application Delivery Platform that allows for the enhancement of functionality and longevity using the app store or apps you create in-house.

Our cloud SWAP has been vetted as one of the best solutions to threats such as cross site scripting (XSS), SQL injections, and Distributed Denial of Service. Cloudbric's logic-based SWAP, which includes pattern matching, semantic, heuristic analysis, and core rulesets, is fully automated and simple to use. This means that there is no need to update security policies or sign signatures often. Private WAF deployments can also be customized with customization options. Our service ensures your website. Your website will remain online and be protected from distributed denial-of-service attacks (DDoS). Cloudbric actively blocks layers 3, 4 and 7 DDoS attacks that can scale up to 20Tbps*

MyDiamo was developed by Penta Security Systems (APAC leader in encryption technology) and is available to all for noncommercial use. Enterprises and organizations who require additional features can obtain a commercial license. Index searching is possible with column-level encryption or partial encryption - Minimal system performance changes guaranteed - Compatible with open-source DBMS such as MySQL, MariaDB and Percona - GDPR/PCI DSS/HIPAA compliant - Code modification is not required, it works parallel at the engine level

WEDOS Protection offers a comprehensive security platform that combines advanced DDoS mitigation, CDN acceleration, and smart traffic filtering to safeguard websites against a wide range of cyber threats. It defends against large-scale volumetric attacks as well as sophisticated application-layer exploits like botnets and L7 attacks. Utilizing a global network of edge servers, the WEDOS Global infrastructure monitors and manages traffic in real time for optimal security and performance. Key features include DNS protection, a Web Application Firewall (WAF), HTTPS proxy, smart caching, and multiple anti-bot filters, all integrated to create a strong, multi-layered defense system. The solution is designed for easy deployment without requiring any changes to website code. It ensures high availability and low latency, even when under attack. WEDOS Protection is suitable for high-traffic websites, e-commerce projects, agencies, IT administrators, and hosting providers. This platform balances strong security with improved website speed and reliability.

DDoS-GUARD has been a leader in the DDoS protection and content delivery market since 2011. We offer services using our own network, which includes scrubbing centers with sufficient computing and channel capacity to process large volumes of traffic. This is a departure from most other companies. We don't resell services from other companies and claim them as our own. Cyber threats are increasing in today's digital world. The number of DDoS attacks is also increasing in line with the latest trends. The attacks become more complex, volumetric, and diverse. We are constantly changing traffic scrubbing algorithms, increasing channel capacities, and adding computational resources to traffic processing centres. This allows us to not only protect our customers from all known DDoS attacks but also detect and block any anomalous network activity that was previously unknown.

open-appsec is an open-source initiative that builds on machine learning to provide pre-emptive web app & API threat protection against OWASP-Top-10 and zero-day attacks. It can be deployed as add-on to Kubernetes Ingress, NGINX, Envoy and API Gateways. The open-appsec engine learns how users normally interact with your web application. It then uses this information to automatically detect requests that fall outside of normal operations, and sends those requests for further analysis to decide whether the request is malicious or not. open-appsec uses two machine learning models: 1. A supervised model that was trained offline based on millions of requests, both malicious and benign. 2. An unsupervised model that is being built in real time in the protected environment. This model uses traffic patterns specific to the environment. open-oppsec simplifies maintenance as there is no threat signature upkeep and exception handling, like common in many WAF solutions.

ArvanCloud CDN consists of tens to PoP sites at important locations around the globe to deliver online content to users, from the nearest geographical point at the highest quality and speed. You can create unlimited cloud servers with ArvanCloud Cloud Computing infrastructure in just a few clicks. You can create multiple cloud storage disks per server and manage your cloud data center communications with Firewall and private or public networks. ArvanCloud allows you secure any type of data stored on Cloud Storage. You can access a reliable storage system anywhere in the world and have no worries about data loss. ArvanCloud Container-Based Platform as a Service conforms to Kubernetes standards. You are only a few commands away from an operational product with ArvanCloud Container-Based Platform as a Service.

BunkerWeb represents a cutting-edge, open-source Web Application Firewall (WAF) designed for modern web security needs. As a fully functional web server built on NGINX, it ensures that your web services are inherently "secure by default." This tool integrates effortlessly into various environments, including Linux, Docker, Swarm, and Kubernetes, and offers complete configurability through an intuitive web interface for those who prefer it over command-line options. In essence, it simplifies the complexities of cybersecurity, making it accessible for all users. Additionally, BunkerWeb includes essential security features in its core system, while also allowing for easy enhancement through a flexible plugin architecture, ensuring that it can adapt to a wide range of security requirements.