What Is Web Application Firewall (WAF)?

A Web Application Firewall (WAF) is a type of firewall that monitors and filters HTTP/HTTPS traffic traveling to and from web apps. Web application firewalls protect apps from various cyber threats (e.g., cross-site forgery, cross-site scripting (XSS), file inclusions, SQL injections, etc.). Organizations deploy a WAF as hardware, software, or a cloud-based service.