This is why I try to put everything behind NGINX with basic auth. Unfortunately not everything works well that way but in this case I suspect that this is made unexploitable by anyone without the password.
"Fortunately" some "white hat" hacker contacted us last year about another Metabase exploit. I gave him a 30 USD tip and ended up doing exactly what you are suggesting.
Now I'm glad that means I don't need to interrupt my vacation to fix this thing right now.
https://www.zeit.de/digital/datenschutz/2021-08/cdu-connect-...
- https://www.golem.de/news/connect-app-cdu-verklagt-offenbar-... - https://www.heise.de/news/Modern-Solution-Anklage-gegen-Aufd...