Morgikan

I would say it reached a better service position in the early 2000s with the rise of broadband (1.5Mbps to 3.0Mbps) internet speeds.

Prior to that, you still had IRC and BBS, but there was a divide between filesize and your ability to download that filesize within reason. There also existed a divide between what was accessible to technical users vs everyone else. Non-technical users might copy 3.5 floppies or cassettes but weren’t present in the internet space. Broadband opened the door for services like Napster, Kazaa, and Limewire which granted everyone access.

That service model was so successful to the point that it completely altered the music industry and how people bought music (ex. iTunes).

It would depend on having access to misconfigured permissions or docker.sock like when you chain containers to manage other containers. Because you have access to docker.sock and that socket can send API calls to the docker daemon (which is run from root) those commands would inherit the same level of access. An attacker could make the API call to mount /:/root and then access the host filesystem.

It’s just an example of how even though the container might not have anything worthwhile, it can be used to laterally move and open another door.

My biggest concern is pivoting. Specific to Jellyfin, many users are using docker, but do not isolate the user so the daemon is operating as root. With that setup, an attacker could mount the host filesystem to the container and would own the host from that container.

Again, for the linux mention, the answer is pivoting. Many machines use Tailscale. If one of those machines were to be compromised using Tailscale’s default ACL, they would be able to move laterally through the network without issue. At that point, it would be possible to modify existing nodes (ex. subnet routers, exit nodes, etc) or even add additional rogue nodes.

The question of why people care is tricky. Why should you care if your networked printer is using out of date firmware? It likely isn’t storing personal information, right? It’s a prime target because it’s easy, poorly monitored, and opens another door. A lot of infosec is just keeping doors shut so other doors don’t get opened.

If the goal is doing this in a simple fashion, then use Tailscale funnels (https://tailscale.com/docs/features/tailscale-funnel). Funnels automate the process and act as a reverse proxy into specific servers within your tailnet.

The downside is there is no authentication to funnels, so whatever you’re running (Jellyfin in this case so that’s not an issue) needs it’s own authentication setup. You might consider running fail2ban on that machine and have it watch for login attempts, but otherwise that is the simplest setup I think you could do.

I had pfSense running on an old Core 2 Duo machine from around 2010 when I worked in MSP. You can run it on just about anything.

The only trouble I had was when I switched to gigabit+ service and had snort running. Snort is single-threaded and that CPU just could not keep up. Suricata would be a better choice given it’s natively multi-threaded, but the real limitation there was my setup and not pfSense.

Bob Saget would roll in his grave if he heard about your addiction.