A web application firewall (WAF) sits between your application and the internet, filtering, monitoring, and blocking malicious HTTP and HTTPS traffic before it reaches the server. SafeLine is a self-hosted WAF that works as an HTTP/HTTPS reverse proxy built on nginx: it receives traffic for the original website, removes malicious requests, and forwards safe traffic to the upstream application ( https://docs.waf.chaitin.com/en/GetStarted/AddApplication ). Its documented protections cover SQL injection, XSS, code injection, OS command injection, CRLF injection, LDAP injection, XPath injection, RCE, XXE, SSRF, path traversal, backdoors, brute force, HTTP floods, and bot abuse ( https://docs.waf.chaitin.com/en/home ).

To write meaningful allow and deny rules for one application, you first need a working install and a correctly proxied app. The steps below follow the official setup flow.

Deploy the WAF

Check the host.…