WAF
Web Application Firewall: a security layer that filters and blocks malicious HTTP traffic.
A WAF (Web Application Firewall) is a specialized firewall that sits in front of a web application and inspects every HTTP request for malicious patterns. It protects against common attacks like SQL injection, cross-site scripting (XSS), file inclusion, and other OWASP Top 10 vulnerabilities. Unlike a traditional firewall that works at the network level (IP addresses and ports), a WAF understands HTTP and can analyze URLs, headers, cookies, and request bodies. Cloudflare's WAF is responsible for error 1020 (Access Denied) when a rule matches a request.
Related terms
See also
Referenced on
- Brute-force defense for wp-login.php
- Cloudflare Error Codes (5xx, 1xxx) and Fixes
- How to Identify and Manage Web Crawlers: A Sysadmin's Guide to robots.txt, AI Bots, and SEO Crawlers
- Privacy Policy - DNS Checker
- Redirect Checker
- What Happens When One DNS Provider Goes Down: The Hidden Fragility of TLD Ecosystems