ModSecurity Open Source WAF vs Qualys Web Application Firewall

ModSecurity Open Source WAF and Qualys Web Application Firewall take different approaches to web application security. Consider your team's expertise and infrastructure preferences when evaluating these options.

View ModSecurity Open Source WAF Review View Qualys Web Application Firewall Review

ModSecurity Open Source WAF and Qualys Web Application Firewall take fundamentally different approaches to web application security. Understanding your infrastructure and team capabilities will help determine which approach fits your needs.

Overview

ModSecurity Open Source WAF and Qualys Web Application Firewall are both popular web application firewall solutions. This comparison will help you understand the key differences and choose the right one for your needs.

The original open source WAF engine powering countless applications, offering unmatched flexibility for those willing to manage their own security infrastructure.

Cloud-managed WAF from Qualys that integrates with their vulnerability scanning platform, enabling one-click virtual patching of discovered vulnerabilities. Note — product was decommissioned September 2024.

Quick Comparison

Feature	ModSecurity Open Source WAF	Qualys Web Application Firewall
Overall Rating	4.0/5	3.0/5
Free Tier	Yes	No
Pricing Model	Free (Open Source)	Subscription, per-asset licensing (product decommissioned)
Ease of Use	2.5/5	3.2/5
Value for Money	4.8/5	2.5/5
Support	3.0/5	3.5/5
Open Source	Yes	No
Platforms	Apache, Nginx, IIS, Kubernetes (via Ingress), Docker, any platform via libmodsecurity	VMware, Hyper-V, Docker, AWS, Azure, Google Cloud Platform
Compliance	N/A (varies by implementation)	PCI DSS, SOC 2, FedRAMP, ISO 27001 (Qualys platform level)

Pricing Comparison

ModSecurity Open Source WAF

Model: Free (Open Source)

Free Tier Available

Community Edition

Free

Commercial Support

Varies by vendor

View full pricing →

Qualys Web Application Firewall

Model: Subscription, per-asset licensing (product decommissioned)

Qualys WAF (Decommissioned)

Previously subscription-based

View full pricing →

Features Comparison

ModSecurity Open Source WAF

OWASP Core Rule Set
Comprehensive, community-maintained rule set providing protection against OWASP Top 10 and more.
Custom Rules
Powerful SecRule language for creating custom detection logic based on any request/response attribute.
Real-Time Request Analysis
Inspect and analyze every HTTP transaction with access to full request and response data.
Audit Logging
Detailed logging of security events for forensics, compliance, and monitoring.
Virtual Patching
Create temporary rules to protect against vulnerabilities while permanent fixes are developed.
Data Loss Prevention
Inspect response bodies to prevent sensitive data leakage.

Qualys Web Application Firewall

WAS Integration
Automatically generate WAF rules from Qualys Web Application Scanning results for one-click virtual patching.
Cloud-Managed Appliance
Virtual appliance deployed locally but managed centrally through the Qualys Cloud Platform.
Custom Security Policies
Flexible policy engine with reusable rules and templates for common platforms and custom applications.
Pre-Built CMS Policies
Out-of-the-box protection policies for WordPress, Joomla, Drupal, SharePoint, and Outlook Web Application.
Security Event Analytics
Detailed dashboards with traffic summaries, threat trends, and drill-down capabilities for incident investigation.
Local Traffic Processing
Application traffic stays within your environment for minimal latency and full data control.

Which One Is Right for You?

The best WAF depends on your specific requirements, infrastructure, and team expertise.

ModSecurity Open Source WAF

You need: Security teams with WAF expertise, organizations with strict budget constraints, those needing maximum customization, educational purposes
You want to start with a free tier
You prefer open-source solutions
You're using: Apache, Nginx, IIS, Kubernetes (via Ingress), Docker, any platform via libmodsecurity

Learn more →

Qualys Web Application Firewall

You need: Historical reference; previously suited for Qualys platform customers wanting integrated vulnerability management and WAF
You're using: VMware, Hyper-V, Docker, AWS, Azure, Google Cloud Platform

Learn more →

We recommend evaluating both options with a trial or free tier before committing. Consider your existing infrastructure, team expertise, compliance requirements, and budget.

Frequently Asked Questions

Which is better for startups: ModSecurity Open Source WAF or Qualys Web Application Firewall?

ModSecurity Open Source WAF offers a free tier while Qualys Web Application Firewall does not, which may be important for early-stage startups. Qualys Web Application Firewall scores higher for ease of use (3.2/5), which is valuable for smaller teams. Consider your immediate security needs and growth plans when choosing.

Which has better support: ModSecurity Open Source WAF or Qualys Web Application Firewall?

Qualys Web Application Firewall has a higher support rating (3.5/5) compared to ModSecurity Open Source WAF (3.0/5). However, support quality can vary based on your plan tier - enterprise customers typically receive more responsive support from both providers. Consider evaluating support during a trial period.

Which is easier to implement: ModSecurity Open Source WAF or Qualys Web Application Firewall?

Qualys Web Application Firewall scores higher for ease of use (3.2/5) versus ModSecurity Open Source WAF (2.5/5). The actual implementation effort depends on your existing infrastructure and team expertise.

Which is more cost-effective: ModSecurity Open Source WAF or Qualys Web Application Firewall?

ModSecurity Open Source WAF offers a free tier while Qualys Web Application Firewall requires a paid plan. ModSecurity Open Source WAF scores higher for value (4.8/5). Total cost depends on your traffic volume, required features, and support level needs.

Which works better with AWS: ModSecurity Open Source WAF or Qualys Web Application Firewall?

Qualys Web Application Firewall explicitly supports AWS while ModSecurity Open Source WAF's AWS integration may vary. Consider whether native AWS integration or cross-cloud portability matters more for your use case.