CVE-2026-45135: 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…

PriorityP353high8.1CVSS 3.1

AVNACHPRNUINSUCHIHAH

EPSS

0.40%

31.7th percentile

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. This vulnerability is fixed in 2.11.3.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
caddyserver	caddy	—	—
caddyserver	caddy	>= 2.7.0 < 2.11.3	2.11.3
github.com	caddyserver_caddy_v2	>= 2.7.0 < 2.11.3	2.11.3

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