zlacker

>>jakels+(OP)
> The Reddit post I’d seen earlier? That guy got completely owned because his container was running as root. The malware could: [...]

Is that the case, though? My understanding was, that even if I run a docker container as root and the container is 100% compromised, there still would need to be a vulnerability in docker for it to “attack” the host, or am I missing something?

>>V__+N4
If the container is running in privileged mode you can just talk to the docker socket to the daemon on the host, spawn a new container with direct access to the root filesystem, and then change anything you want as root.

>>easter+hw
Notably, if you run docker-in-docker, Docker is probably not a security boundary. Try this inside any dind container (especially devcontainers): docker run -it --rm --pid=host --privileged -v /:/mnt alpine sh

I disagree with other commenters here that Docker is not a security boundary. It's a fine one, as long as you don't disable the boundary, which is as easy as running a container with `--privileged`. I wrote about secure alternatives for devcontainers here: https://cgamesplay.com/recipes/devcontainers/#docker-in-devc...

>>CGames+cO
Containers are never a security boundary. If you configure them correctly, avoid all the footguns, and pray that there's no container escape vulnerabilities that affect "correctly" configured containers then they can be a crude approximation of a security boundary that may be enough for your use case, but they aren't a suitable substitute for hardware backed virtualization.

The only serious company that I'm aware of which doesn't understand that is Microsoft, and the reason I know that is because they've been embarrassed again and again by vulnerabilities that only exist because they run multitenant systems with only containers for isolation

>>flamin+V11
Virtual machines are never a security boundary. If you configure them correctly, avoid all the footguns, and pray that there's no VM escape vulnerabilities that affect "correctly" configured VMs then they can be a crude approximation of a security boundary that may be enough for your use case, but they aren't a suitable substitute for entirely separate hardware.

Its all turtles, all the way down.

>>vel0ci+T52
Yeah, in some (rare) situations physical isolation is a more appropriate level of security. Or if you want to land somewhere in between, you can use VM's with single tenant NUMA nodes.

But for a typical case, VM's are the bare minimum to say you have a _secure_ isolation boundary because the attack surface is way smaller.