sudneo, 1 year ago

You already mentioned the most important things.

I will add, at the cost of being pedantic:

• build the image properly, or use good images. This means limit dependencies as much as possible, as minimal images as possible (less updates due to CVEs, less tooling).
• do not mount host volumes, if you really have to, use a dedicated subpath owned by the user of the container. Do not use homedirs etc.
• do not run in host namespaces, like host network etc. Use port mapping to send traffic to the container.

If you want to go hardcore:

• analyze your application, and if feasible, build and use a more restrictive seccomp profile compared to the default. This might limit additional syscalls that might be used during an exploitation but that your app doesn’t need.
• run falco on the node. Even with the default set of rules (nothing custom), many exploitation or posts-exploitation steps would be caught, such as “shell spawned” etc.