Top 10 Web Application Firewalls (WAFs) for 2024

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Protecting your business from malicious activity has never been more challenging. 

Cyber attacks are on the rise – with almost 10,000 incidents being reported since January – and malicious actors are becoming more sophisticated in their attacks thanks to the increasing prevalence of AI in the cybercriminal underground. 

With the threat higher than ever before, many organizations are being forced to increase their cybersecurity spending and implement new security defences to keep hackers out. 

One increasingly prevalent defence employed by businesses is web application firewalls (WAFs), which are crucial to keeping online businesses and web applications secure in today’s ever-evolving threat landscape.

What is a web application firewall?

A web application firewall (WAF) is a security tool that acts as a shield for your web applications. It sits in front of your web applications and monitors the traffic going back and forth –  filtering, inspecting and blocking any malicious activity it detects.

Unlike a regular firewall that operates at the network layer, WAFs function at the application of the OSI model.  They act as a reverse proxy, sitting in front of your web servers so all web traffic destined for your application goes through the WAF before reaching, which inspects and filters it before passing legitimate requests onto the server.

Based on the inspection results, WAF enforces pre-configured security policies which define how to handle different types of traffic. If a threat is detected, the WAF blocks it and prevents it from reaching your web application and potentially causing harm. 

How do WAFs protect against external threats?

WAFs are equipped with a database of known attack signatures. They compare incoming requests against these signatures to identify and block malicious patterns associated with common attacks like SQL injection or XSS.

When the WAF detects a potential threat based on its inspection, it takes action to block it. This can involve blocking the IP address of the attacker, dropping the malicious request, or challenging the user with a CAPTCHA to differentiate them from a bot.

Advanced WAFs can analyze request characteristics beyond just signatures. They look for unusual patterns in data formats, request frequency, or origin to identify suspicious behaviour that might indicate a zero-day attack.

WAFs also typically log all the activity they encounter, including blocked attacks and allowed traffic. These logs can be valuable for security audits, identifying trends in attack attempts, and fine-tuning your WAF's policies for optimal protection.

The three types of WAFs

There are three main types of web application firewalls (WAFs), which differ in their deployment and management style:

1. Cloud-based WAF

This is a subscription-based service offered by cloud security providers. The WAF resides in the cloud and filters traffic before it reaches your web servers. Cloud-based WAFs are easy to set up and manage as the service provider handles maintenance and updates. They are also scalable, and able to adjust to fluctuating traffic volumes. However, they may introduce latency since traffic travels to the cloud for inspection.

2. Hardware-based WAF

This type of WAF is a dedicated physical appliance installed on your network. It offers high performance and low latency because traffic inspection happens locally. Hardware-based WAFs provide granular control but require upfront investment and ongoing maintenance for the physical appliance.

3. Software-based WAF

This option comes as software that can be installed on your web servers or in virtual machines. It offers more flexibility than hardware WAFs and can be more cost-effective. However, software-based WAFs can consume server resources and require additional configuration and security management.

Best Web Application Firewalls (WAFs)

best web application firewall waf

There are a variety of WAFs and WAF vendors on the market today, each of which can help you keep malicious actors away from your website. But, as is usually the case with these things, not all of these WAFs are made the same. 

In this list, we’re counting down ten of the best web application firewalls (WAFs) available today based on their range of features and popularity with users. 

NetScaler API Protection

NetScaler API Protection is a cloud-based web application firewall (WAF) that acts as a comprehensive shield for your APIs and safeguards them from a range of threats and malicious activity. Boasting a powerful, always-on distributed denial-of-service (DDoS) defence system, the firewall absorbs and deflects DDoS attacks aimed at overwhelming your APIs and preventing legitimate traffic from reaching them.  It also includes a robust WAF engine that inspects API traffic for vulnerabilities and suspicious patterns. This allows it to identify and block common attacks like SQL injection, cross-site scripting (XSS), and API-specific threats like broken object-level authorization.

NetScaler API Protection goes beyond traditional WAFs by offering built-in bot management capabilities, to help you distinguish between legitimate users and automated bots that might be malicious or trying to scrape data. You can also define granular security policies for your APIs, allowing you to control access based on factors like IP address, user role, and API request parameters. By leveraging these features and its focus on APIs, NetScaler API Protection stands out as a powerful and user-friendly WAF solution for securing your critical APIs in today's threat landscape.


Reblaze is a cloud-based, all-in-one WAF and security platform designed to protect websites, web applications, and APIs. The platform goes beyond traditional WAF functionalities by offering a comprehensive suite of features to safeguard your online presence. It comes with a powerful WAF engine that combines signature-based detection with advanced behavioural analysis to identify and block known and zero-day attacks and can handle multi-layered DDoS attacks across network layers, ensuring your web applications remain accessible during attacks. The platform also offers dedicated protection for APIs, safeguarding them from common API vulnerabilities and unauthorised access attempts.

Being cloud-based, Reblaze offers automatic scaling to adapt to fluctuating traffic volumes, and its online user-friendly interface simplifies security management. The platform also includes features like anti-scraping to prevent content theft, Content Delivery Network (CDN) for improved performance, and real-time traffic control for granular control over traffic flow. This comprehensive security suite is delivered through a convenient cloud-based platform, enabling Reblaze to cater to the needs of businesses seeking robust and user-friendly protection for their web applications and APIs.

Sucuri WAF

Sucuri WAF is a powerful web application firewall that filters and inspects all incoming traffic before it reaches your web server, safeguarding your website from malicious attacks and vulnerabilities. The firewall utilizes a robust WAF engine that employs a combination of signature-based detection and anomaly detection techniques, allowing it to identify and block common attacks like SQL injection, XSS, and zero-day threats.

Sucuri WAF goes beyond just blocking attacks, too. It also offers website malware scanning to identify and remove any malicious code that might have infiltrated your website. The platform’s virtual patching feature helps address security vulnerabilities in outdated software by patching them virtually at the WAF level. This provides an extra layer of protection while you work on applying official updates.

Broadcom's Symantec WAF

Symantec WAF is a security solution designed to protect web applications from various threats.  The solution utilizes a combination of signature-based detection for known threats and anomaly detection to identify suspicious traffic patterns, helping block common attacks like SQL injection and XSS  while also offering some protection against zero-day threats.  It also offers robust authentication and authorization features and can integrate with your existing authentication systems and enforce granular access control policies for your web applications. There are detailed logging and reporting functionalities too, allowing you to monitor security events, identify trends in attack attempts, and improve your WAF's effectiveness over time.

Unlike some cloud-based WAFs, Symantec WAF offers on-premises and hybrid deployment options, making it ideal for organizations with specific security requirements or compliance needs that necessitate on-premises control. And while not a core feature, it can also be integrated with additional Broadcom solutions for DDoS mitigation capabilities, providing a more comprehensive security posture. It can also optionally use a positive security model, allowing only traffic matching pre-defined patterns of legitimate requests, offering strong protection but requiring careful configuration

Azure Application Gateway

Microsoft Azure Application Gateway is a cloud-based service within the Azure platform that goes beyond just web application firewalls (WAF). It acts as a multi-purpose application delivery controller (ADC), offering a range of functionalities to manage traffic for your web applications. AGW excels at load-balancing traffic across multiple web servers in your Azure environment. It distributes incoming traffic based on various factors like round robin or least connections, ensuring optimal performance and high availability for your applications. Integrated within AGW, the WAF engine also safeguards your web applications from common attacks like SQL injection, XSS, and OWASP Top 10 threats, using signature-based detection and anomaly analysis to identify and block malicious traffic.

Along with its powerful safeguarding capabilities, AGW provides comprehensive monitoring and analytics capabilities. You can track application health, identify potential issues, and gain insights into traffic patterns. This, combined with its application delivery features, makes it a compelling choice for organizations seeking a comprehensive and scalable approach to web application security and traffic management within the Azure ecosystem.


Qualys WAF is a powerful WAF security solution offered by Qualys that resides entirely in the cloud. The platform leverages the security expertise of Qualys researchers to provide a robust set of pre-configured security policies. These policies are designed to block common attacks like SQL injection, XSS, and OWASP Top 10 threats, allowing you to create and customize your own security policies to address specific application needs.  The WAF provides comprehensive reporting on security events too. You can gain insights into the types of attacks your applications are facing, identify trends and m

Qualys WAF integrates with the Qualys Cloud Platform, which continuously analyzes security threats and updates the WAF's ruleset with the latest information. This ensures your WAF stays up-to-date and can effectively block even new and emerging threats (zero-day attacks). You can also create reusable profiles for common settings like web server pools, health checks, SSL certificates, and HTTP protocol filters. This simplifies configuration for multiple web applications with similar security requirements. By providing this robust feature set, user-friendly management, and continuous security updates, Qualys WAF stands out as a reliable and powerful solution for protecting your web applications in today's dynamic threat landscape.

Cloudflare Application Security and Performance

Cloudflare Application Security and Performance is a cloud-based web WAF that sits at the edge of Cloudflare's massive global network, acting as a security shield for your web applications and APIs. The platform uses a powerful WAF engine that combines signature-based and anomaly-detection techniques to block common attacks like SQL injection, XSS, and API-specific vulnerabilities.  Integrated with Cloudflare's DDoS protection capabilities, the WAF also helps absorb and deflect DDoS attacks aimed at overwhelming your applications. It leverages Cloudflare's extensive global network, and the WAF filters traffic closer to users, reducing latency and offering exceptional scalability to handle traffic spikes.

Along with its powerful incident response features, Cloudflare WAF incorporates advanced bot detection and mitigation features to distinguish between legitimate users and malicious bots that might be scraping data or disrupting your applications. This combination of WAF, DDoS protection, bot management, and API security provides a layered defence against various threats.  Cloudflare WAF integrates seamlessly with other Cloudflare services, simplifying security management to make it accessible to users with varying technical expertise. Cloudflare WAF stands out as a powerful and comprehensive solution for securing your web applications and APIs within the Cloudflare ecosystem.

Radware Cloud WAF

Radware Cloud WAF is a cloud-based web application firewall (WAF) service designed to protect your web applications from a vast array of threats. The platform boasts a powerful WAF engine that employs a multi-layered approach to security, combining signature-based detection for known threats with behavioural analysis to identify and block zero-day attacks. it goes beyond traditional WAF functionalities too, offering dedicated protection for APIs that allows it to secure your APIs against common API vulnerabilities and unauthorised access attempts. It also integrates with Radware's DDoS protection solutions., helping it mitigate distributed denial-of-service attacks aimed at overwhelming your applications and preventing legitimate traffic from reaching them.

Along with its powerful WAF functionalities, Radware Cloud WAF provides real-time security analytics and threat intelligence feeds, empowering you to gain insights into potential security threats and make informed decisions about your overall security posture. This makes it a powerful and feature-rich WAF suitable for organizations seeking comprehensive web application security with advanced threat protection capabilities. 

Imperva WAF

With a host of powerful WAF functionalities for tackling complex threats, Imperva WAF is one of the leading web application firewalls available today. The solution is designed to safeguard your web applications from a vast array of threats. It acts as a security shield positioned in front of your web applications, inspecting and filtering all incoming and outgoing traffic while identifying and blocking malicious activity before it reaches your applications, Imperva WAF helps maintain application security and functionality. Minerva goes beyond traditional WAF perimeters by offering RASP functionalities that monitor application runtime behaviour from within the application itself, providing additional security insights and protection against vulnerabilities that might exist within the application code.

Imperva WAF provides one of the industry’s most comprehensive security analytics and reporting in the WAF space. You can gain insights into attack attempts, user behaviour, and application health, allowing you to make informed decisions about your security posture. The WAF integrates seamlessly with Imperva’s protection solutions too, helping you mitigate distributed denial-of-service attacks before they impact your business. 


AWS WAF is a cloud-based web application firewall (WAF) service offered by Amazon that’s widely considered to be one of the best WAF solutions available today. The solution acts as a security layer positioned in front of your web applications hosted on AWS, using Web ACLs to define the security rules that govern incoming traffic. You can create multiple Web ACLs and associate them with different web resources based on their specific security requirements, and the solution can also automatically block IP addresses that exhibit suspicious behaviour, such as making excessive requests in a short period. You can even configure AWS WAF to block traffic originating from specific countries or regions, making it easy to reduce the risk of geographically targeted attacks.


AWS WAF provides a library of pre-configured rules that address common web vulnerabilities like SQL injection and XSS attacks, and you can customize these rules or create entirely new ones to tailor the security posture to your specific application needs. The solution uses a pay-as-you-go model too, making it a budget-friendly option for organizations with dynamic traffic patterns. This, paired with its ease of use, scalability, and native integration with other AWS services make it a compelling choice for securing web applications within the AWS environment.