Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, Caddy's HTTP "path" request matcher is intended to be case-insensitive, but when the match pattern contains percent-escape sequences ("%xx") it compares against the request's escaped path without lowercasing. An attacker can bypass path-based routing and any access controls attached to that route by changing the casing of the request path. Version 2.11.1 contains a fix for the issue.