How do i you decide whats safe to run
I recently ran Gossa on my home server using Docker, mounting it to a folder. Since I used rootless Docker, I was curious - if Gossa were to be a virus, would I have been infected? Have any of you had experience with Gossa?
Personally, I do believe that rootless Docker/Podman have a strong enough security boundary for personal/individual self-hosting where you have decent trust in the software you’re running. Linux privilege escalation and container escape exploits fetch decent amounts of money on the exploit market, and nobody’s gonna waste them on some people running software ending in *arr when Zerodium will pay five figures for a local privilege escalation or container escape. If you’re running a business or you might be targeted for whatever reason (journalist or whatever) then that doesn’t apply.
If you want more security, there are container runtimes that do cooler security stuff under the hood, like Firecracker/Kata Containers implementing a managed VM, or Google’s gVisor which very strongly intercepts kernel syscalls and essentially reimplements Linux in userspace. Those are used by AWS and Google Cloud respectively. You can integrate those into Docker, though not all networking/etc options are supported.
I generally say that containers and traditional UNIX users are good enough isolation for “mostly trusted” software. Basically I know that they aren’t going to actively try to escalate their privilege but may contain bugs that would cause problems without any isolation.
Of course it always depends on your risk. If you are handing sensitive user data and run lots of different services on the same host you may start to worry about remote code execution vulnerabilities and will be interested in stronger isolation so that a RCE in any one service doesn’t allow escalation to access all data being processed by other services on the host.