What is ModSecurity and How It Works

Web applications are constantly exposed to threats such as: SQL injection Cross-site scripting (XSS) file inclusion attacks bot scanning To defend against these threats, many organizations deploy a Web Application Firewall (WAF) . One of the most widely used open-source WAF solutions is ModSecurity . In this article, we’ll cover: What ModSecurity is How it works internally Its strengths and limitations How modern WAFs compare What is ModSecurity? ModSecurity is an open-source Web Application Firewall (WAF) that sits between users and web applications to inspect HTTP traffic. It can be deployed with popular web servers such as: Apache Nginx IIS Its main purpose is to: monitor HTTP requests and responses detect malicious payloads block or log suspicious traffic Think of ModSecurity as a rule-based security engine for web applications. Where ModSecurity Sits in the Architecture ModSecurity works as a filtering layer in front of your application. Client │ ▼ ModSecurity (WAF) │ ▼ Web Server