A Web Application Firewall (WAF) is a security system that aims to protect web apps and sites, using a set of rules that filter HTTP traffic. It monitors and blocks any malicious or abnormal behaviors coming from the Internet and going towards web apps.

A Web Application Firewalls (WAF) software solution should be capable of dealing with OWASP’s top ten. Some of these common web attacks include:

SQL injections.
Cross-site forgery.
DDoS attacks,
Cross-Site Scripting (XSS).
and other types of attacks.

Still, web apps are vulnerable to zero-day attacks or might have unique traffic patterns, so a WAF must look beyond the common web attacks.

More advanced WAF solutions can provide automated defenses and managed services to control these sets of rules. These advanced WAF solutions give access to expert security teams, edge networks, threat intelligence, AI/ML analytics, traffic monitoring, and more.

In this post, we’ll go through the best WAF vendors that provide the most comprehensive web app security:

Sucuri Website Firewall. A cloud-based WAF with a large database of attack signatures developed by Sucuri’s expert research.
Imperva Cloud WAF. A component of an integrated defense suite, including CDN, DDoS mitigation, bot protection, and more.
Barracuda Web Application Firewall. It uses positive signature-based rules and robust analysis/detection capabilities to defend your assets.
AppTrana Managed Web Application Firewall A fully-managed WAF designed to automatically scan, find vulnerabilities, and patch applications. AppTrana is bundled with a CDN and managed security rules.
AWS WAF. A cloud-based WAF that leverages other AWS services to detect and mitigate web attacks.
F5 Advanced WAF. It uses a combination of threat intelligence and ML to protect web apps from data breaches, zero-day, and OWASP’s top ten risks.
Cloudflare WAF. A cloud-based WAF that leverages a massive CDN, provides automatic protection from app’s vulnerabilities and allows customized rules.
Akamai Kona Site Defender. Built on Akamai Intelligent Edge Platform and designed to protect web apps, sites, and API from OWASP’s top ten, L7 DDoS, and zero-day attacks.
Radware Cloud WAF. A cloud-based WAF capable of responding against the most sophisticated and damaging web threats.

Our methodology for selecting the best web application firewalls:

Choosing the best web application firewalls includes various factors to add extra protection to the website. Below, we have listed some of the proven methodologies that you must consider to pick the best tool to fulfill your organization's needs.

First, you must understand your website's requirements, such as traffic volume, type of data handled, and potential threats.
Explore various WAF providers and their features, like SQL injection and cross-site scripting.
Integration is important when using tools wisely; consider your infrastructure, content management system (CMS), or hosting provider.
Try testing the WAF's performance and its impact on your website's speed and responsiveness.
Look for customization options that fit your specific needs.
Review Security Updates and patches.
You must also consider the responsiveness of customer support if you need help.
Lastly, consider costs that fit your budget without compromising security.

The Best Web Application Firewalls

1. Sucuri Website Firewall

Sucuri’s WAF is a cloud-based web application firewall that improves the detection of OWASP’s top ten. It comes with its own set of rules, but also allows you full customization. The predefined rules are powered by Sucuri’s continuous research on threats and mitigation strategies.

Key Features:

DDoS Protection: Safeguards websites from denial of service threats and, at the same time, ensures its availability.
Malware Removal: Automatically deletes malware that weakens the defense and operating systems.
Brute Force Protection: Blocks brute force attacks and prevent the perpetration of repetitive unauthorized access attempts.
Performance Optimization: Interfaces with a Content Delivery Network (CDN) to facilitate quicker site speed and startup time.

Why do we recommend it?

Sucuri Website Firewall is recommended for its comprehensive approach to security, combining malware prevention, DDoS protection, and performance optimization. It's particularly notable for its ability to enhance website performance while ensuring robust security measures are in place. The ease of setup and continuous monitoring capabilities make it an excellent choice for businesses seeking a reliable, hands-off security solution.

Unique Feature:

When the Sucuri service is defending other websites, it updates and maintains a large database of attack signatures. Sucuri will apply the same mitigation strategy (rules) that help them solve another issue. Additionally, Sucuri’s WAF gives you access to their global CDN to mitigate DDoS attacks, speed up load time, or increase availability.

Who is it recommended for?

This solution is ideal for small to medium-sized businesses (SMBs) and website owners who may not have extensive security expertise in-house. Its user-friendly interface and managed security services make it a great option for those looking for an effective, low-maintenance security solution to protect their online presence.

Pros:

Includes Various Security Options: Suggests a wide array of security layers including hostile input, DDoS attacks, and hacking attempts.
User-Friendly and Quick Setup: The interface is user-friendly and has a straightforward setup and system management.
Quick Detection and Remediation: The time taken for the detection and immediate reaction to the threats is critical and limits the adverse consequences.
SEO Ranking Protection: The hackers will have difficulty bypassing the security since the search engines won't blacklist their website due to a security issue.

Cons:

External CDN and Firewall: The CDN and the firewall are other services that even if they are external will also not work for everyone who wants to have their privacy or data residency requirements met.

Price: Three licenses: Basic ($199.99/yr), Pro ($299.99/yr), and Business ($499.99/yr). Sign up to request a free consultation.

EDITOR'S CHOICE

Sucuri Website Firewall is our top choice when it comes to finding the best web application firewall. You never have to worry about any cyber attack because this tool always ensures your website stays up and running. Your website will eventually handle more traffic because of Its Anycast Network spreads across the globe. It uses top-notch hardware and technology in its data centers, and performance is guaranteed. Plus, it detects and blocks malicious bots and hackers automatically, keeping your site safe from harm. With Sucuri, you can be confident that your website will be available and performing properly, regardless of the dangers it faces.

Download: Get a 30-Day Free Trial

OS: Cloud-Based

2. Imperva Cloud WAF

Imperva cloud-based WAF protects your websites and apps from the newest and most sophisticated web threats. It protects assets regardless of their location, either on-premise or in the cloud.

Imperva Research Labs is actively searching and discovering new threats including the OWASP Top 10 and beyond. Imperva’s security experts monitor new vulnerability landscapes from external sources and propagate updated WAF rules on a daily basis.

Key Features:

Advanced Bot Protection: Applies advanced techniques to detect such traffic and separates into good and bad categories.
API Security: The building up of APIs with specialized defenses against all kinds of exploits. In such circumstances, the last thing a company wants is to get into costly public litigation seeking damages for infringement, misleading or wrong advertising, or unjustified claims against competitors or their products.
Real-Time Threat Intelligence: Global data extraction accentuates the identification and attenuation of new dangers as they emerge.
Custom Security Rules: Permits you to create tailor-fitted regulations that occasionally solves unique security needs. Write an 8 to 10-sentence paragraph that conveys the given message.

Why do we recommend it?

Imperva Cloud WAF stands out for its advanced bot protection, real-time threat intelligence, and automated web application and API protection features. It offers a high level of accuracy in threat detection, scalability to handle high traffic volumes, and detailed analytics for insights into security threats. These capabilities make it a powerful tool for protecting against a wide range of web application attacks.

Unique Feature:

The Imperva Cloud WAF is a key component of the integrated defense suite, Imperva Application Security. The WAF is empowered by other apps and services like CDN, DDoS protection, load balancing, and bot protection. These apps and services are found at every single edge server.

Who is it recommended for?

This solution is best suited for medium to large enterprises that face complex security challenges and require advanced protection for their web applications and APIs. Organizations with significant web traffic that seek a scalable, comprehensive security solution would find Imperva Cloud WAF to be an excellent fit.

Pros:

Capable of Handling High Traffic: Handles high traffic without affecting performance as volume scales up.
Business Intelligence System: This includes a business intelligence system to generate reports and forecasts capable of pinpointing specific threats to traffic and other disruptions or problems.
Supports Multiple Security Options: Vulnerabilities like SQL injection, cross-site scripting (XSS), and others will be involved as well.
Fast Content Delivery: Gives users a better quality experience through low latency and quicker delivery of content.

Cons:

Might Not be Suitable for SMEs: Equipment with greatly enhanced features and capabilities are more expensive, so it is not very suitable for small to medium enterprise businesseses.

Price: Contact the Imperva team to get a quote and a free demo.

3. Barracuda Web Application Firewall

Barracuda is a leader in enterprise-grade, cloud-ready security solutions. They develop the Barracuda WAF to protect your web, mobile, API applications, and website from attacks. The WAF knows how to safeguard against the OWASP Top 10, plus zero-day risks, data leaks, and DDoS layer 7 attacks.

Barracuda WAF can be implemented in any size of business. It is available on appliances, as WAF-as-a-Service, for private cloud, and as a virtual machine.

Key Features:

Data Leak Prevention: All sensitive data is obfuscated before transmission to the outside world through an automation process.
Adaptive Profiling: Mimics real traffic and security policies, and are artificially created in the new environment.
Automated Vulnerability Remediation: Identifies and patches holes left behind by vulnerabilities that hackers can exploit.
SSL Offloading: Runs SSL encryption and decryption processes, relieving unnecesary processing burdens from the web server.

Why do we recommend it?

Barracuda Web Application Firewall is recommended for its extensive security features, including data leak prevention, automated vulnerability remediation, and advanced DDoS protection. It's particularly adept at stopping data breaches and providing strong access control mechanisms. The integration with existing infrastructure and the ability to meet regulatory compliance requirements make it a solid choice for businesses focused on data security and compliance.

Unique Feature:

Barracuda WAF combines positive signature-based rules with robust analysis and detection capabilities. So, it is capable of not only stopping known attacks but also zero-day vulnerabilities and data loss.

Who is it recommended for?

It is highly recommended for businesses of all sizes that prioritize data protection and need to comply with regulatory standards such as PCI DSS, HIPAA, or GDPR. Organizations that require granular control over their web application security, as well as those looking for a solution that can easily integrate into their existing security infrastructure, would benefit greatly from the Barracuda Web Application Firewall.

Pros:

Supports Multi-Layer Protection: Multi-layer protects apps up against web app attacks.
Supports Data Security Protocols: It permits setting the requirements for data security protocols like PCI DSS, the payment card industry security standard.
Includes Automation: Automated functionalities are the solution to avoid regular human updates and their respective patches.
SSL Computation and Integration: This accelerates SSL computation and integrates the Content Delivery Network functionalities, which, in turn, leads to better efficiency.

Cons:

Potentially Overwhelming Features: An expanse of functions and individual ways to use them can lead to constraints for new users or small teams.

Price? Request a price or get a free Barracuda WAF evaluation.

4. AppTrana Managed Web Application Firewall

AppTrana Managed WAF is developed by Indusface, a leader in web security apps. The WAF is backed up by a managed security service, that provides 24/7 security experts to help you develop vulnerability patching rules.

The AppTranna WAF is optimized out-of-the-box with a set of rules, developed by Indusface after thousands of website security assessments. Users can use these rules or create/customize as required.

Key Features:

24/7 Managed Security: Not only continuous protection with 24 hours monitoring and management, but also regular health checks for both the smart devices and the users.
Instant Threat Patching: Instant detection of and reparation of vulnerabilities within the disguise of the next update.
DDoS Protection: Provides extensive protection against DDoS attacks aimed at damaging the whole system.
Web Acceleration: The CDN integration is used to ensure seamless and fast page loads and enhance performance.

Why do we recommend it?

AppTrana is recommended for its managed security services that offer continuous protection, instant threat patching, and DDoS protection, alongside performance enhancement through CDN. This solution shines with its managed service model, providing businesses with expert monitoring and management of their web security posture, reducing the need for in-house security expertise.

Unique Feature:

AppTranna WAF is one of the only few web security tools that puts application’s protection first. It will automatically scan and identify the app’s vulnerabilities and install patches as necessary.

Who is it recommended for?

AppTrana is ideal for small to medium-sized businesses that may lack dedicated security teams but need comprehensive, managed web security solutions. It's also a great fit for businesses looking for a combination of enhanced performance and robust security without the complexity of managing these aspects in-house.

Pros:

Managed Service: Ensuring professional competence and monitoring.
Dynamic Threat Protection: Vulnerable to new attacks; all the more components are in quick reaction.
Performance Boost: Users are provided with an enhanced experience by animating CDN to facilitate faster content delivery.
Comprehensive Coverage: Protects employees against a wide range of web application attacks and vulnerabilities.

Cons:

Lack of Customized Security: The conventional approach means that you're only as good as your coding ability on a forced system; if you have special security requirements, you're likely looking at limited levels of control.

Price: Premium ($399/app/month) and Advanced ($99/app/month). Test AppTrana with a 14-day free trial.

5. AWS WAF

AWS WAF is a cloud-based WAF that protects web apps and APIs from common web attacks that affect the availability or consume excessive resources.

Key Features:

Customizable Web Security Rules: It enables users to produce and edit their own rules concerning web traffic filtering of IP addresses, HTTP headers, and the URI strings.
Integration with AWS Services: Seamlessly weaves itself into Amazon CloudFront, Application Load Balancer, and Amazon API Gateway.
Real-Time Metrics and Logs: Provides extra details with Amazon CloudWatch, which makes it easier to track web traffic and find out who the threat is.
Automated Bot Control: Employs advanced spam rule sets to smartly filter out typical bot traffic, underscoring the pivotal role of the internet and social media in shaping modern communication, learning, and entertainment.

Why do we recommend it?

AWS WAF is highly recommended for its flexibility and integration capabilities within the AWS ecosystem. It offers customizable web security rules, real-time visibility, and automated bot control, making it a powerful tool for protecting web applications against common exploits. The pay-as-you-go pricing model also makes it accessible for businesses of all sizes.

The AWS WAF comes with a pre-configured ruleset, that allows you to start using the WAF, right out of the box. These rules can deal with the OWASP top 10 security risks. But you can also define your own security rules that filter specific traffic patterns.

You can deploy AWS WAF on and with other AWS services like:

Amazon CloudFront (a powerful CDN).
Application Load Balancer
Amazon API Gateway for your REST APIs,
AWS AppSync for your GraphQL APIs.
AWS CloudWatch to monitor incoming traffic.
Amazon Kinesis Firehose to tune rules based on log data.

Unique Feature:

AWS is a leader in public cloud computing, CDNs, and APIs. By itself, AWS WAF is not as powerful as other WAFs in the market, but when you combine it with other AWS services, the WAF can turn out as one of the best.

Who is it recommended for?

This solution is particularly well-suited for businesses already leveraging AWS services, as it seamlessly integrates with Amazon CloudFront, Application Load Balancer, and Amazon API Gateway. It's also ideal for businesses of any size that require a customizable and scalable web application firewall solution.

Pros:

Flexible Pricing: Pay-per-visit pricing lets agencies with large levels of users or heavy traffic through the budgeted cost.
Deep Integration with AWS Ecosystem: Effectively, the application works best for those existing within the Amazon Web Services (AWS) ecosystem.
Scalable: This native feature can expand with your application to seamlessly handle bursts of traffic.
Customization and Control: Supports complex rule options that allow customization to perfectly correspond to a security requirement.

Cons:

Beginners Could Find it Difficult: There is a possibility that AWS novices will face some challenges involved in the establishment and monitoring.

Price: AWS uses a pay-as-you-use model. You can get an estimate with the AWS price calculator.

6. F5 Advanced WAF

F5 Advanced WAF is a comprehensive web app, site, and API protection against OWASP's top ten and other sophisticated attacks. It protects your assets with behavioral analytics, API inspection, proactive defense from malicious bots and automation attacks, and application-level data encryption.

F5 Advanced WAF is available as an appliance, as software (to deploy in a hypervisor, data center, or private cloud), as-a-Service, and via public clouds (AWS, Azure, and GPC).

Key Features:

Behavioral Analytics: Based on machine learning technology, it can discern the normal application behavior and distinguish it from the anomalies.
Anti-Bot Protection: Identifies and prevents bots and malicious traffic through whilst users do not notice anything.
Advanced Threat Protection: Helps secure the algorithm against complex threats such as application layer DDoS, API abuse, and more.
Fraud and Abuse Prevention: Monitors and prosecutes any cases of identity theft, fraud, or abuse that occurs anywhere in the world.

Why do we recommend it?

F5 Advanced WAF is recommended for its advanced threat protection capabilities, including behavioral analytics, anti-bot protection, as well as fraud and abuse prevention. It leverages machine learning to enhance threat detection and response, making it effective against sophisticated and emerging threats. Its comprehensive security posture and customizable features make it a powerful defense mechanism.

Unique Feature:

The F5 Advanced WAF combines Machine Learning (ML), threat intelligence (F5 Threat Campaigns), and deep application expertise.

Who is it recommended for?

This solution is best suited for medium to large enterprises that face sophisticated security challenges and need advanced protection features. Organizations that value the integration of behavioral analytics and machine learning for enhanced security will find F5 Advanced WAF to be an excellent choice.

Pros:

Prevents Web and App Cyber Attacks: It is suitable for protecting against a variety of web and application attacks, and its advanced functionality goes beyond the basic services.
Behavior Analytics: Improves threat detection and response system with the assistance of behavior analytics.
Connected Services: Purposely built for the purpose of keeping services connected and at a low level of latency under the worst-case assault.
Extensive Customization: Offers a wide variety of configurations to customize the security policies to take effect only when and where needed.

Cons:

Complicated Configuration: The added abilities and features may attract IT professionals to buy them but prove to be complicated to configure and manage.

Price: Contact the F5 sales department to get a quote or try F5 Advanced WAF for free.

7. Cloudflare WAF

Cloudflare WAF is an intelligent and scalable solution. It protects web apps, sites, and APIs from common OWASP top ten, and sophisticated DDoS attacks.

The WAF comes with a dashboard where you can build and customize firewall rules and integrate it with the Terraform API. Every request made to your web assets is inspected against a defined set of rules and CloudFlare's threat intelligence. The Cloudflare WAF also integrates Machine Learning (ML) and signature-based heuristics for intelligent analysis.

Key Features:

Integrated Performance and Security: Provides both CDN equipment and WAF application to increase website speed while implementing security actions.
DDoS Protection: Equips deep insights into sources of DDoS attacks of any scale.
Automated Threat Intelligence: Uses the biggest network quantity to do a good job of identifying and stopping threats immediately.
Simplicity: Eliminates the difficulty involved in setting up and managing the security mechanisms manually through a dashboard interface, which is easy to use.

Why do we recommend it?

Cloudflare WAF is recommended for its ease of use, integrated performance and security features, comprehensive DDoS protection, and automated threat intelligence. It combines security with performance optimization via its global CDN, providing users with a straightforward setup and automatic scaling to handle traffic spikes. The community intelligence feature offers enhanced threat detection and mitigation.

Unique Feature:

Cloudflare is pretty popular for having one of the largest CDNs in the world. It comprises hundreds of data centers distributed across the globe, in +100 countries. This CDN is optimal for providing protection against volumetric attacks (DDoS) coming from botnets or automated scripts.

Who is it recommended for?

Cloudflare WAF is an excellent option for businesses of all sizes looking for a balance between security and website performance. It's particularly beneficial for those seeking a user-friendly solution that offers both robust web application protection and global content delivery capabilities.

Pros:

Easy to Install: Slightly tangled but functional hardware that's easy to install.
Don't Need I/O Operations: Scales real-time as traffic increases, thus eliminating I/O operations.
Improved Website Speed: It improves website access speed everywhere in the world and ensures its safety.
Improve your Business User Base: Benefits like gaining a huge user base assisted in thwarting both cyber attacks and breaches.

Cons:

May Need Extra Configuration: While the ability to define security rules may work for some users, others might need to explore a wider range of configuration options.

Price: There are four pricing plans: Free, Pro ($20/month), Business ($200/ month), and Enterprise.

8. Akamai Kona Site Defender

Akamai Kona Site Defender is a highly scalable cloud-based WAF designed to safeguard web apps, APIs, and websites from common web vulnerabilities and sophisticated attacks like L7 DDOS.

Kona Site Defender uses a proprietary anomaly detection engine with input from security experts, researchers, and ML algorithms. The proprietary pre-configured rules are tested against live traffic to avoid false positives and negatives and efficiently block attacks.

Key Features:

Layered Defense: Combines proactive and reactive defenses.
Adaptive Rate Controls: The user controls the system dynamically in order to avoid the loss of access caused by DDoS attacks.
Advanced Bot Management: Separates friendly or malicious bots and executes the proper measures accordingly.
Cloud Security Intelligence: Utilizes massive data analytics to raise the security level through global internet traffic patterns.

Why do we recommend it?

Akamai Kona Site Defender is highly recommended for its comprehensive protection strategy that combines proactive and reactive defenses to ensure robust security. With features like adaptive rate controls, advanced bot management, and cloud security intelligence, it offers a dynamic and scalable solution capable of defending against an extensive range of web threats. Its global network ensures that protection is both widespread and efficient, providing not just security but also improved application performance.

Unique Feature:

Akamai is a leader in CDN services and cloud security solutions. It focuses on delivering security at the edge, closer to where an attack originated and far away from your application servers. Akamai has unmatched visibility of the threat landscape. Its WAF rules are triggered 178 billion times a day, which gives them an advantage on threat intelligence.

Who is it recommended for?

This tool is particularly well-suited for large enterprises and organizations with high-traffic websites that require global coverage and scalability. Companies in industries facing sophisticated and high-volume web attacks, such as finance, retail, and media, will find Akamai Kona Site Defender's capabilities especially beneficial. It's also a great choice for businesses looking for a solution that supports seamless integration with existing CDN services for performance optimization.

Pros:

World-Wide Reach: Utilizes Akamai's world-wide reach for both security and distribution supply grid.
Quick Response: Adaptability is its notable advantage, combined with quick response with adaptive technologies to emerging security threats.
Handles Peak Load Traffic: When handling peak incoming traffic load, efficiency is maintained at a constant level of performance.
Efficient: Delivers information in deep-dive form with all required inputs as a major component.

Cons:

Limited Customization Rules: Despite its strong security capabilities, the platform's limited customization for rules and policies may restrict detailed security fine-tuning compared to other solutions.

You can test Akamai’s Web Application Protector (a simplified DDoS and application-layer security) for free for 30 days.

9. Radware Cloud WAF

The Radware Cloud WAF is an adaptive security solution that protects from OWASP's top 10, zero-day, and emerging threats. It detects new web applications and protects them using its automatic rule generation engine.

Radware provides a cloud services portal that unifies WAF and other solutions including DDoS protection and access to Radware’s Emergency Response Team.

Key Features:

Behavioral-Based Detection: Utilizes machine learning to identify and block threats based on user behavior, rather than relying solely on known signatures.
Auto-Policy Generation: Automatically generates security policies based on traffic analysis to provide immediate protection.
SSL Inspection: Decrypts and inspects encrypted traffic for hidden threats, ensuring comprehensive security coverage.
Cloud-Based Distributed Denial of Service (DDoS) Protection: Offers integrated DDoS protection to safeguard against large-scale attacks aimed at disrupting service availability.

Why do we recommend it?

It is recommended for its advanced approach to web application security, utilizing behavioral-based detection and machine learning to effectively combat zero-day and sophisticated threats. Its auto-policy generation simplifies the complex process of security management, making it easier for organizations to maintain a high level of protection without constant manual intervention. The addition of SSL inspection ensures that even encrypted traffic is scrutinized for threats, providing a comprehensive security posture.

Unique Feature:

Radware is a global leader in integrated application delivery solutions. It was ranked by Gartner as the top API and high-security use case in 2020. The company is known for solving the most sophisticated web threats, and DDoS, with its cloud WAF and DDoS protection solutions.

Who is it recommended for?

This solution is ideal for businesses of all sizes that are particularly concerned with emerging web security threats and require a flexible, cloud-based solution that can scale with their needs. It's well-suited for companies in sectors where security needs are dynamic and where maintaining an advanced, proactive defense against evolving threats is critical. Organizations that value ease of use and automation in managing their web security will find Radware Cloud WAF to be an excellent choice.

Pros:

Uses Machine Learning Algorithm: Employs sophisticated machine learning algorithms to detect and mitigate zero-day and unknown threats effectively.
Auto-Policy Feature: The auto-policy feature reduces the complexity of configuring and managing security policies.
Inspects SSL Traffic: Inspection of SSL traffic ensures that encrypted communications do not bypass security checks.
Highly Scalable: Being cloud-based, it can easily scale to meet the demands of growing traffic and is flexible enough to protect applications wherever they are hosted.

Cons:

Technical Expertise Required: While SSL inspection is a strength, managing SSL certificates and configurations can be complex and require additional expertise.

Price? Contact the Radware team to get a quote.

How to choose the right WAF?

Look for solutions that give you protection from OWASP's top ten.

Most of the solutions shown in this post will give you protection from OWASP's top ten and might even go beyond it. They accomplish “more,” by solving zero-day attacks and identifying abnormal traffic using AI and ML. Additionally, all the tools give you access to threat intelligence and security experts that help identify even the most sophisticated attacks.

If you don’t know which way to go, you can test the WAF waters for free with some services like AppTrana, F5 Advanced WAF, or Akamai.