Advisories for Golang/Github.com/Dunglas/Frankenphp package

In worker mode under concurrency, FrankenPHP can hand a PHP session id from one request to another when PHP's session extension is loaded as a shared module instead of being statically linked into the FrankenPHP binary. A request presenting Cookie: session=A can have session_id() resolve to B (a different concurrent client's id) or to a stale id from a previous request served by the same worker thread.

The splitPos() function in cgi.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 FrankenPHP into treating a non-.php file as a .php script. In any deployment where the attacker can place content into a file served by FrankenPHP (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path …

FrankenPHP’s CGI path splitting logic improperly handles Unicode characters during case conversion. The logic computes the split index (for finding .php) on a lowercased copy of the request path but applies that byte index to the original path. Because strings.ToLower() in Go can increase the byte length of certain UTF-8 characters (e.g., Ⱥ expands when lowercased), the computed index may not align with the correct position in the original string. …

When running FrankenPHP in worker mode, the $_SESSION superglobal is not correctly reset between requests. This allows a subsequent request processed by the same worker to access the $_SESSION data of the previous request (potentially belonging to a different user) before session_start() is called.

Vulnerability in base Docker images (PHP, Go, and Alpine) not automatically propagating to FrankenPHP images. FrankenPHP's container images were previously built only when specific version tags were updated or when manual triggers were initiated. This meant that if an upstream base image (such as Alpine Linux or official PHP/Go images) received a security patch under an existing tag, the FrankenPHP image would remain on the older, vulnerable version of those …