lacework-global-343

note

This policy has been deprecated in favor of lacework-global-654.

See Adjusted Rules - CIS Amazon EKS 1.1.0 for further details.

4.2.7 Minimize the admission of containers with the NET_RAW capability (Automated)

Profile Applicability

• Level 1

Description

Do not generally permit containers with the potentially dangerous NET_RAW capability.

Rationale

Containers run with a default set of capabilities as assigned by the Container Runtime. By default, this can include potentially dangerous capabilities. With Docker as the container runtime the NET_RAW capability is enabled which may be misused by malicious containers.

Ideally, all containers should drop this capability.

There should be at least one PodSecurityPolicy (PSP) defined which prevents containers with the NET_RAW capability from launching.

If you need to run containers with this capability, this should be defined in a separate PSP and you should carefully check RBAC controls to ensure that only limited service accounts and users are given permission to access that PSP.

Impact

Pods with containers which run with the NET_RAW capability will not be permitted.

Audit

Get the set of PSPs with the following command:

kubectl get psp

For each PSP, check whether NET_RAW is disabled:

kubectl get psp <name> -o=jsonpath='{.spec.requiredDropCapabilities}'

Verify that there is at least one PSP which returns NET_RAW or ALL.

Remediation

Create a PSP as described in the Kubernetes documentation, ensuring that the .spec.requiredDropCapabilities is set to include either NET_RAW or ALL.

References

https://kubernetes.io/docs/concepts/policy/pod-security-policy/#enabling-pod-security-policies
https://www.nccgroup.trust/uk/our-research/abusing-privileged-and-unprivileged-linux-containers/