{"schemaVersion":3,"id":"CVE-2026-45135","aliases":["UBUNTU-CVE-2026-45135","DEBIAN-CVE-2026-45135","GHSA-m675-2p33-xv9g","GO-2026-5492"],"status":"published","duplicateOf":null,"title":null,"description":"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 flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. 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