top of page

F5 WAF vs. CloudFlare WAF vs. open-appsec - Which Is the Best Tool to Protect Your Web Application a

To be sincere, selecting the best web application firewall that meets your business or organization's needs will not be easy, especially when choosing between popular tools like F5 and Cloudflare WAF.

This is true if you want a WAF that offers robust security and protects your website from known and unknown attacks. And if you want WAF that is affordable, easy to configure, deploy and manage, and offers integration with the modern environment.

This article compares the features of F5 WAF and Cloudflare WAF by looking at how best they help protect your web app and API. Also, we will introduce a new web application security tool called open-appsec.

F5 Advanced WAF vs. CloudFlare WAF vs. open-appsec

The table below shows the features of F5 advanced WAF, Cloudflare WAF, and open-appsec.


Cloudflare WAF




ML-based. No signature needed




Zero-day protection (Text4Shell, Log4Shell, Spring4Shell, etc.)




API protection











Yes (premium feature)


NGINX, NGINX Ingress, Envoy Add-On




Kubernetes Ingress




Gateway VM for AWS, Azure, and VMWare



Enterprise version


Declarative configuration and deployment




SaaS Web-based Event Management & Dashboards








Code and Price



Yes (30 days free trial)






Pros and Cons of F5 Advanced WAF

These are the pros and cons of F5 Advanced WAF based on reviews by people who have used it.



F5 Advanced WAF secures your web app and API against zero-day attacks.

F5 Advanced WAF could improve resource usage because it is CPU intensive.

Defend against vulnerabilities like CVEs, OWASP Top 10, SQL injection, cross-site scripting, etc.

Compatibility with multiple cloud environments needs improvement. Also, stability and scalability need to be improved.

Protect your web resources credentials from theft and prevent man-in-the-browser theft.

No zero-day pre-emptive protection as the solution is based on signatures.

Detects and mitigates layer 7 DDoS attacks by analyzing traffic behaviors using machine learning.

F5 Advanced WAF is a security solution that protects your apps, APIs, and data from the most common cyber-attacks like layer DDoS attacks, zero-day vulnerabilities, and bad bots.

It provides robust protection by enabling security automation for DevOps and AppDev and can be deployed across multi-cloud, hybrid, and on-site environments in different forms.

Here are some features of F5 Advanced WAF:

Provides WAF security. BIG-IP Advanced WAF offers protection against common attack types like OWASP Top 10 and known CVEs. Aside from that, it also protects from SQL/PHP injection and zero-day attacks. F5 WAF has a dedicated dashboard showing the mitigation level applied against the latest version of OWASP vulnerability categories. Also, the dashboard shows a security score to enable you to view policy coverage status and improve protection.

Provides protection against layer 7 DDoS. Since most layer 7 DDoS attacks are stealth and may go undetected, F5 WAF automatically learns the app behavior and combines the behavior heuristic of traffic to identify DDoS conditions. It will, in turn, create Dynamic signatures that are then deployed for real-time protection.

Provides API security. F5 WAF safeguards APIs, XML, and secure GraphQL. You can easily augment your API Gateways with F5 Advanced WAF to seal API management gaps and enable security for all use cases. It also enables your business to defend against API-specific risks with controls for securing GraphQL APIs, XML, GWT APIs, and Rest APIs.

Defend against bad bots. It protects against drive-by bots and other vulnerability exploitation. It leverages a combination of challenge and behavior-based techniques that identify and filter bot traffic. Stopping bad bots will help you eliminate many attack opportunities and defend your web app and API.

Leaked credential check. F5 Advanced WAF offers an add-on, F5 Leaked Credential Check, that helps prevent credential-based attacks using automated detection and mitigating leaked, breached, and fraudulent credentials. It will enable your SecOps team to perform evasive actions like blocking access where credentials are compromised.

Pros and Cons of Cloudflare WAF

These are Cloudflare WAF reviews by users who have used the tool.



Cloudflare WAF offers automatic protection from vulnerabilities like OWASP Top 10 and zero-day attacks.

No zero-day pre-emptive protection as the solution is based on signatures.

It provides real-time reporting.

Requires manual tuning of signatures

Cloudflare WAF prevents SQL injection, cross-site scripting, and malware.

Customizing rules can be difficult when doing it the first time.

You can set custom rules to block requests from specific IP addresses and countries.

Cloudflare WAF is a web app and API security tool that protects your assets from cross-site scripting, SQL injection, and zero-day attacks. It also safeguards web resources against OWASP-identified vulnerabilities and threats that target your application layer. When integrated with Cloudflare DDoS protection, it can block millions of attacks daily.

As a cloud-based service, Cloudflare WAF needs no hardware or software, and you can deploy the web application firewall with a single click and customize it to meet your needs. Cloudflare WAF integration with other services ensures that you get additional functionality for free.

It also runs the ModSecurity rule set, enabling you to protect your web application and API against critical security flaws identified by OWASP. Some Cloudflare WAF features are listed below.

Automatic protection. Cloudflare WAF offers automatic protection from diverse threats with default rule sets and extensive customization. This provides Layer 7 protection integrated with DDoS mitigation.

Web and API security. Cloudflare WAF ensures that your web and API are always protected from common and unknown attacks. It deters attacks like SQL injection and cross-site scripting without additional latency.

Also, you can add a WAF policy to SSL-encrypted traffic requests without uploading a certificate or buying expensive hardware. To secure your web resources, Cloudflare WAF can block/allow traffic from IP addresses to protect against hackers from certain countries or IPs.

Customize rule set. To protect against vulnerabilities, Cloudflare WAF allows you to import existing rule sets to maintain existing protection. Also, it has a core OWASP ModSecurity rule set that protects against OWASP vulnerabilities. And it ships with platform-specific rule sets for major e-commerce and CMS platforms with no extra fee.

Real-time reporting. Cloudflare WAF offers real-time logging that gives instant insight into what is happening.

Pros and Cons of open-appsec

Are you looking for a way to block attacks on your web application before they happen? open-appsec uses machine learning to continuously detect and preemptively block threats before they can do any damage. Our code has also been published on GitHub, and the effectiveness of our WAF has been successfully proven in numerous tests by third parties. Try open-appsec in the Playground today.

open-appsec Pros

open-appsec Cons

Automatically identify and deter threats with zero false positives.

It is a new security initiative.

Offers a full IPS Engine that monitors web requests to prevent intrusion.

There isn't a lot of information about it on the internet.

Integrate with modern environments like the public cloud, CI/CD workflow, etc.

open-appsec has a small community of users.

Easy configuration and management; no signature upkeep required.

open-appsec is an open-source, automated 'install and forget' security initiative developed to detect and stop attacks automatically using machine learning. It requires little management without manually tuning the setting to adjust to each vulnerability.

Once installed, open-appsec will use machine learning to analyze requests made to your web app or API and block malicious requests while allowing good ones. It has two security best practices - Detect/Learn mode or Prevent mode.

With those best practices, open-appsec safeguard your application and API from known and unknown top-layer web attacks like zero-day vulnerabilities, distinguish real users from bots, prevent common attacks and CVEs, and validates API inputs.

open-appsec stands out from the crowd because it can preemptively safeguard your web resources from attacks like OWASP Top 10, malicious bots, and zero-day exploits with no further adjustments. And its default setting block Log4Shell, Text4Shell, and Spring4Shell.

It is free and open-source, making it easy for DevOpsSec, IT professionals, etc., to use and expand the code. Deploying open-appsec is easy because you can add it to NGINX, Kubernetes, API Gateways, and Envoy.

You can use open-appsec for free with no limit on the number of web traffic filters. Also, you can always get the premium version if you want advanced protection, like bad bot detection and log cloud storage.

The open-appsec playground teaches how to use the tool to protect your web resources. Users can play around the playground by learning how to detect and prevent attacks. The Kubernetes and NGINX playgrounds are available, so you can choose the option that matches your environment.

With the playground, you will learn how to:

  • Attack the demo application by doing SQL injection.

  • Deploy open-appsec on Kubernetes or NGINX, depending on your environment.

  • Do SQL injection again to ensure the security is well-implemented and effective.

  • Connect to the SaaS Web-Based Management.

Features of open-appsec

open-appsec attribute include automatic threat detection, Kubernetes and NGINX integration, open-source, free, zero-day exploits protection, API security, and easy management.

1. Prevent Zero-Day Attacks

open-appsec safeguards your web resources from known and unknown threats and prevents credential theft and loss of your customers' data. An example of unknown threats it protects against is zero-day exploits.

2. Provides Web and API Security

You can use open-appsec to protect your assets from vulnerabilities like cross-site scripting, SQL injection, unauthorized access, etc. It does this preemptively by using its ML-based engine to scan for threats continuously.

3. Integrate with Kubernetes and NGINX

Depending on your environment, you can integrate open-appsec with Kubernetes, Envoy, NGINX, and API Gateways. Aside from that, open-appsec also integrates with modern environments like the public cloud.

4. Web Behavioral Anti-Bot

open-appsec protects against bots that can slow down your application performance and other vulnerability exploitation. It uses its web behavioral anti-bot to identify and filter bad bots. Deterring bad bots will help eliminate many attacks and defend your web application.

5. Uses Machine Learning

With machine learning, open-appsec preemptively detects and deters threats from vulnerabilities like OWASP and prevents zero-day attacks. No need to adjust the configuration.

6. Free and open-source

You can use the free version of open-appsec to safeguard your web application. The free version has no limit on the number of traffic analyzed. And if you want additional protection like an anti-bot or cloud log storage, you can get the paid version. The source code is available on GitHub for anyone to use.

7. Easy to Maintain

Unlike other web application firewalls, maintaining open-appsec is not an issue. It does not need constant adjustment or signature upkeep because it automatically identifies and deters threats.


Which is the best security tool to protect your web application and API? We have considered the features of F5 Advanced WAF, Cloudflare WAF, and open-appsec, and now it is time for our verdict.

You can choose F5 Advanced WAF if you want a security solution to protect your app, data, and API against attacks like OWASP Top 10. Also, it offers robust protection by enabling security automation for AppDev and DevOps and can be used across multi-cloud, on-site, and hybrid environments.

If you want a web application firewall that can be deployed with a few clicks and integrates with other services for additional functionalities, Cloudflare WAF is the right option. Cloudflare WAF safeguards against attacks like SQL injection, cross-site scripting, and blocklist traffic from malicious IP addresses.

open-appsec is the best choice because it detects threats automatically and integrates with Kubernetes, NGINX, and public clouds. Aside from that, open-appsec protects against zero-day attacks automatically without constant updates. Besides, it is open-source and has a free version.

Frequently Asked Questions

What Is Cloudflare WAF?

The Cloudflare web application firewall is an advanced security portfolio that keeps web apps and APIs secure, thwarting DDoS attacks, malicious traffic, and bot attacks.

Is F5 a Firewall or Load Balancer?

F5 WAF is an advanced web application firewall that safeguards your apps, APIs, and data from attacks like DDoS, zero-day vulnerabilities, and bad bots. Also, it detects and mitigates layer 7 DDoS attacks by analyzing traffic behaviors using machine learning.

Experiment with open-appsec for Linux, Kubernetes or Kong using a free virtual lab

bottom of page