CVE-2026-34965: Cockpit CMS Authenticated Remote Code Execution via Collections

Cockpit CMS contains an authenticated remote code execution vulnerability in the /cockpit/collections/save_collection endpoint that allows authenticated attackers with collection management privileges to inject arbitrary PHP code into collection rules parameters. Attackers can inject malicious PHP code through rule parameters which is written directly to server-side PHP files and executed via include() to achieve arbitrary command execution on the underlying server.