Best Web Application Firewalls (WAF) for Linux of 2025

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.

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.

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.

Fortinet, a global leader of cybersecurity solutions, is known for its integrated and comprehensive approach to safeguarding digital devices, networks, and applications. Fortinet was founded in 2000 and offers a variety of products and solutions, including firewalls and endpoint protection systems, intrusion prevention and secure access. Fortinet Security Fabric is at the core of the company's offerings. It is a unified platform which seamlessly integrates security tools in order to deliver visibility, automate, and real-time intelligence about threats across the network. Fortinet is trusted by businesses, governments and service providers around the world. It emphasizes innovation, performance and scalability to ensure robust defense against evolving cyber-threats while supporting digital transformation.

Our engineers are specialists at working in sectors where zero downtime is critical. Since 2003, we’ve been building a reputation for delivering ultra-reliable, easy to deploy and effortlessly scalable applications that are trusted by solution partners, system integrators and end-users alike. Our focus on forming long-lasting partnerships with industry-leading solution providers in healthcare, storage and print, requires an in-depth understanding of both our partners and their clients’ technical and business practices. The result: unprecedented levels of uptime.

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.

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.

It can be difficult to deliver applications at scale. NetScaler simplifies the process. On-premise is the way to go. Cloud is the future. Hybrid is good. NetScaler will work the same on any platform. NetScaler uses a software-based architectural design, which means that it will behave the same regardless of the ADC form factor. NetScaler can help you deliver applications to hundreds or millions of users, whether they are consumers, employees, or both. NetScaler has become the platform of choice by the world's biggest companies for application delivery and security. NetScaler is used by thousands of organizations around the world, including more than 90 percent Fortune 500 companies, for high-performance app delivery, comprehensive API and application security, and end to end observability.

BunkerWeb, a Web Application Firewall of the next generation and open source (WAF), is a powerful tool. It is a full-featured server that uses NGINX as its backend. This will make your web services "secure by default". BunkerWeb integrates seamlessly with your existing environments, including Linux, Docker Swarm, Kubernetes ...), and is fully configurable. BunkerWeb makes cybersecurity a breeze. BunkerWeb includes primary security features in its core, but can be easily expanded with additional ones using a plugin system).