Lists like the OWASP Top 10 in web application security read like a hacker’s shopping list: broken access control, authentication failures, server-side request forgery…
In response, the WAF market continues to dominate and is expected to grow to $19.75 billion by 2030. Alongside network- and host-based WAFs, cloud WAF solutions are becoming increasingly popular with developers, so let’s explore why.
What are Cloud WAF Solutions?
Cloud Web Application Firewalls (WAFs) are a security service that protects web applications from malicious activities and vulnerabilities. Unlike traditional firewalls that protect a network's perimeter, WAFs focus on protecting the application layer by monitoring and filtering HTTP traffic between the application and the internet.
Apart from cloud WAFs, we can categorize WAF tools into two more categories based on their deployment location and method. These categories define how WAF tools are managed, scaled, and integrated with existing infrastructure.
Cloud WAF vs. Network-based and Host-based WAF Solutions
Cloud WAFs: These are provided by cloud services and deployed in the cloud. This model allows for easy scalability, rapid deployment, and reduced maintenance since the service provider manages the infrastructure and software updates.
Network-based WAFs: These are physical devices deployed within your network. They protect by being strategically placed to inspect incoming traffic before it reaches web applications. However, they require significant upfront investment and ongoing maintenance.
Host-based WAFs: These software solutions can work on your own servers or in the cloud. They're more affordable and flexible than network-based WAFs, but they can require a bit more work to maintain.
Types of Cloud WAF Solutions
Cloud WAF solutions use two primary methods to filter web traffic: blocklist and allowlist WAFs.
Blocklist WAFs: Maintains a list of known malicious sources, patterns, or identifiers. Any incoming traffic matching these criteria is automatically blocked. This approach effectively prevents known threats but may not catch new or unknown threats.
Allowlist WAFs: Only allow traffic from sources, patterns, or identifiers defined as safe. This method offers a higher level of security by ensuring that only verified traffic can access the application. However, it requires more maintenance to update the allowlist and might restrict legitimate traffic if not managed carefully.
Benefits of Cloud WAF Solutions
Enhanced Access Control: WAFs automatically enforce permissions and manage access controls, ensuring only authorized users can interact with your application.
Proactive Vulnerability Detection: Continuous security monitoring allows WAFs to identify and mitigate exploitable vulnerabilities before they escalate.
Scalability: WAFs can quickly scale to meet the demands of growing traffic. This scalability ensures that security measures can keep pace with rapid increases in web traffic.
Cost-Effectiveness: Cloud WAFs can be more cost-effective, especially for small and medium-sized businesses, since they eliminate the need for physical hardware and reduce the workload on IT staff.
Improved Security: Offers protection against a wide range of threats, including DDoS attacks, SQL injection, and cross-site scripting.
Key Features to Look For in a Cloud WAF Solution
HTTP Request Assessment: Look for a WAF that thoroughly examines each HTTP request. It should identify and stop potentially harmful traffic by comparing it against security rules.
Zero-day Attack Protection: Select a WAF solution that protects you against advanced threats like zero-day attacks.
Request and Response Normalization: A good WAF tool should standardize all incoming and outgoing data according to a specific set of rules. It ensures consistent application of security policies.
Machine Learning: Advanced WAF solutions use machine learning models to detect and block anomalies for suspicious activity. WAFs with ML support can adapt to new threats and ensure long-term protection.
10 Top Cloud WAF Solutions
1. AWS WAF
AWS WAF is a fully managed, customizable WAF solution that helps protect web applications against common web exploits. It is ideal for AWS users since it can easily be integrated into existing infrastructure.
Main Features:
Customizable web traffic rules to block common attack patterns.
Real-time metrics and logs for quick response to threats.
Integration with Amazon CloudFront and Application Load Balancer.
Best For: Businesses already invested in the AWS ecosystem looking for easy integration.
Pricing: Pay-as-you-go pricing model based on the usage.
Review: “AWS WAF is the web-based firewall that has built-in DDOS attack protection to stop any DDOS attacks. Also, the AWS support team quickly responds to the queries or concerns raised.”
2. open-appsec
open-appsec is an open-source and ML-driven web application and API security solution designed to automatically protect against OWASP Top 10 attacks like broken access control and security misconfiguration. Furthermore, it pre-emptively protects you against zero-day vulnerabilities since it is not signature-dependent.
Main Features:
Uses ML algorithms to protect against OWASP Top 10 attacks and zero-day threats.
Flexible SSL encryption configuration with forward secrecy ciphers and HSTS.
Low false positives, suitable for primary attack detection/prevention.
Best For: Web applications and API security.
Pricing: Free and open source.
Review: “open-appsec/CloudGuard AppSec protects our web applications and prevents OWASP Top 10 attacks. It is also automatically checked and creates a risk score.”
Cloudflare WAF is a part of Cloudflare's integrated security services. It offers robust defense against a wide array of threats with minimal configuration.
Main Features:
DDoS protection and traffic acceleration through Cloudflare’s global CDN.
Automated and customizable protection rules.
Easy setup with instant updates and a managed ruleset.
Best For: Businesses of all sizes seeking performance and security.
Pricing: Offers a free plan with limited features.
Review: “Cloudflare is one of the best choices for me when it comes to firewall, security, and CDN performance. I have used Cloudflare for a long time to enhance website performance and secure the website.”
Akamai offers robust defense against web and DDoS attacks, utilizing adaptive rate controls and real-time threat analysis.
Main Features:
Protects against large-scale DDoS attacks and web application threats.
Adaptive rate controls to manage bot traffic.
Real-time analytics and insights.
Best For: Enterprises requiring scalable security solutions.
Pricing: Offers a free trial, then it’s by inquiry.
Review: “A 24/7 system that monitors threats around the web apps. Secures every application, including websites, API, and web firewall. Support service is brilliant and helpful.”
Azure WAF is a flexible WAF solution integrated with Azure Application Gateway. It can be deployed in one of three operational modes: detection, prevention, and custom.
Main Features:
Integrated with Azure Application Gateway.
Create custom rules to suit the specific needs of your applications.
Geo-filter traffic to allow or block certain countries/regions
Best For: Organizations that use existing Azure services.
Pricing: No upfront costs, as it’s pay-as-you-go.
Review: “[I like] the different modes and SKUs available to choose from per the requirements. [And the] ability to add Custom Rules along with built-in OWASP rules.”
F5 WAF provides extensive protection with advanced features like bot mitigation and adaptive threat intelligence.
Main Features:
Advanced bot protection and mitigation against OWASP Top 10 security risks.
Adaptive threat intelligence to protect against new and evolving threats.
Scalable and flexible deployment options across environments.
Best For: Large enterprises needing a scalable solution that can adapt to complex environments.
Pricing: By inquiry.
Review: “[It helps] to stop the most critical attacks. The configuration is very complicated; however, [the support team] will help you configure it with more options.”
FortiWeb Cloud WAF is a cloud-based, AI-driven firewall that ensures quick deployment and robust protection for web applications.
Main Features:
AI-based behavioral detection for identifying sophisticated threats.
Easy deployment and management with SaaS-based delivery.
Comprehensive protection against application layer attacks.
Best For: SMEs and enterprises looking for AI-driven security solutions with minimal setup.
Pricing: Subscription-based pricing with various tiers.
Review: “Fortiweb uses clever bot mitigation technologies to detect whether the user is real or not.”
Imperva WAF provides comprehensive protection against the latest threats and regulatory compliance support for applications across various environments.
Main Features:
Real-time protection against web attacks and DDoS.
Automated and customizable security rules.
PCI-compliant data security for sensitive information.
Best For: Businesses of all sizes that prioritize PCI compliance.
Pricing: By inquiry.
Review: “Imperva WAF offers an extremely comfortable admin life with its well-advanced GUI features.”
Barracuda is a robust security solution that protects web applications from various threats, including OWASP Top 10 threats, bots, and DDoS attacks.
Main Features:
Protection against OWASP Top 10 threats, bots, and DDoS attacks.
Advanced threat intelligence with automated updates.
Easy to deploy on-premises or in the cloud, with a straightforward management interface.
Best For: Organizations seeking versatile deployment options and straightforward management.
Pricing: Offers both subscription-based and pay-as-you-go pricing models.
Review: “The Barracuda ATP solution, vulnerability manager, and pre-defined attack rules [offer a] high-security solution.”
10. Radware WAF
Radware offers hybrid cloud and on-premises web application protection with machine learning for immediate threat detection.
Main Features:
Hybrid deployment options for on-premises and cloud environments.
Comprehensive protection against multi-vector attacks.
Machine-learning algorithms for real-time threat detection and mitigation.
Best For: Businesses requiring hybrid deployment flexibility and advanced, adaptive threat protection.
Pricing: Custom pricing depending on deployment and protection needs.
Review: “Radware WAF as a service offers a comprehensive, scalable, and user-friendly solution for safeguarding web applications.”
open-appsec is an open-source project that builds on machine learning to provide pre-emptive web app & API threat protection against OWASP-Top-10 and zero-day attacks. It simplifies maintenance as there is no threat signature upkeep and exception handling, like common in many WAF solutions.
To learn more about how open-appsec works, see this White Paper and the in-depth Video Tutorial. You can also experiment with deployment in the free Playground.
