On 5/4/20 11:35 AM, Matej Tyc wrote:

On 01. 05. 20 4:11, Shawn Wells wrote:

On 4/30/20 12:05 PM, Matej Tyc wrote:

I second to Jan - what I have heard from both of you, Gabe and Trevor, is that we can expect legitimate use cases of containers with elevated privileges that would e.g. influence the kernel by directly setting modules, kernel parameters, time and so on.

From what I see, there is no automated way of how to tell whether a scanned container is meant to be privileged (ntp container will need privileges), or whether it is an omission or an attack attempt. Therefore, I don't see how removing this machine platform could be an improvement. I would expect specialized container profiles that Trevor has just mentioned to come first. Disable of the machine platform denomination makes a positive change only when those profiles are ready.


Fair enough. Is there interest to join the SCAP committees to create new probes that can handle these scenarios?


Let's use the NTP example and let's do a thought experiment to see whether extending SCAP can help:

Consider a system that runs containers, and those containers are supposed not to be privileged except one, which is privileged, because of the NTP service it's supposed to run. You don't want two containers that are privileged and that run NTP, and let's say that in that particular case, you don't want a container that inserts kernel modules.

No machine can read the admin's mind, and it's the admin who knows that only container X is supposed to be privileged, and that only because of NTP, otherwise all remaining containers should run without any privileges.

On another system, admin may need two containers for kernel modules, but none for NTP, and so on.

Is there any other way how to satisfy everybody than to have a profile for unprivileged containers, and specialized profiles for privileged containers?


Is that actually a use case people care about?

If NTP is installed, then make sure it's configured. Not sure thinking needs to go deeper than that.

Let the platform figure out who can run privileged containers. That's a problem of Pivotal/Docker/OpenShift etc. Not a problem of the SCAP content that makes sure the OS is configured.