What is a WAF (Web Application Firewall)?
A Web Application Firewall (WAF) is a security system that monitors, filters, and blocks HTTP traffic to and from a web application. Unlike network firewalls that protect the network layer, a WAF specifically safeguards web applications from attacks targeting vulnerabilities in application code.
Common attacks WAFs protect against include:
- SQL Injection: Attackers inject malicious SQL queries to access or modify databases.
- Cross-Site Scripting (XSS): Attackers inject scripts to steal cookies or manipulate web pages.
- File Inclusion Attacks: Exploiting weaknesses to include malicious files on a server.
Benefits of Using a WAF:
- Prevents attacks from reaching the application.
- Provides detailed traffic logging for forensic analysis.
- Supports compliance with security standards such as PCI DSS.
- Can work with CDNs and reverse proxies for enhanced performance and protection.
Modern WAFs also include AI-driven traffic analysis to detect unusual patterns, helping prevent zero-day attacks. Implementing a WAF is essential for businesses handling sensitive customer data online.