mailcow: dockerized is an open source groupware/email suite based on docker. A security vulnerability has been identified in mailcow affecting versions prior to 2024-04. This vulnerability is a combination of path traversal and arbitrary code execution, specifically targeting the `rspamd_maps()` function. It allows authenticated admin users to overwrite any file writable by the www-data user by exploiting improper path validation. The exploit chain can lead to the execution of arbitrary commands on the server. Version 2024-04 contains a patch for the issue.