CVE-2026-41228

Froxlor is open source server administration software. Prior to version 2.3.6, the Froxlor API endpoint Customers.update (and Admins.update) does not validate the def_language parameter against the list of available language files. An authenticated customer can set def_language to a path traversal payload (e.g., ../../../../../var/customers/webs/customer1/evil), which is stored in the database. On subsequent requests, Language::loadLanguage() constructs a file path using this value and executes it via require, achieving arbitrary PHP code execution as the web server user. Version 2.3.6 fixes the issue.