Specifically these issues: https://github.com/jellyfin/jellyfin/issues/5415
The big one is that video/audio playing endpoints can be used without authentication. However, you have to guess a UUID. If Jellyfin is using UUIDv4 (fully random), then this shouldn’t be an issue; the search space is too big. However, many of the other types of UUIDs could hypothetically be enumerated through brute force. I’m not sure what Jellyfin uses for UUIDs.
Nah, setting non-standard ports is sound advice in security circles.
People misunderstand the “no security through obscurity” phrase. If you build security as a chain, where the chain is only as good as the weakest link, then it’s bad. But if you build security in layers, like a castle, then it can only help. It’s OK for a layer to be weak when there are other layers behind it.
Even better, non-standard ports will make 99% of threats go away. They automate scans that are just looking for anything they can break. If they don’t see the open ports, they move on. Won’t stop a determined attacker, of course, but that’s what other layers are for.
As long as there’s real security otherwise (TLS, good passwords, etc), it’s fine.
If anyone says “that’s a false sense of security”, ignore them. They’ve replaced thinking with a cliche.
Almost like sleep mode on x86 is impossible to do correctly. I’m not even sure Windows does better or worse than Linux on this one.