Mailcow through 2024-11b has a session fixation vulnerability in the web panel. It allows remote attackers to set a session identifier when HSTS is disabled on a victim's browser. After a user logs in, they are authenticated and the session identifier is valid. Then, a remote attacker can access the victim's web panel with the same session identifier.
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-23c8-4wwr-g3c6