CVE-2026-45135: Improper Input Validation

Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct fla...

GHSA-5R3V-VC8M-M96G Caddy: Unicode case-folding length expansion causes incorrect split_path index in FastCGI transport

Summary Caddy's FastCGI path splitting logic computes the split index on a lowercased copy of the request path and then uses that byte index to slice the original path. This is unsafe for Unicode because strings.ToLower can change UTF-8 byte length for some characters. As a result, Caddy can deri...