Cis Ocp V190 5.7.2

CIS Red Hat OpenShift Container Platform Benchmark v1.9.0 - Control 5.7.2

Profile Applicability

• Level: 2

Description

Enable default seccomp profile in your pod definitions.

Rationale

Seccomp (secure computing mode) is used to restrict the set of system calls applications can make, allowing cluster administrators greater control over the security of workloads running in the cluster. Kubernetes disables seccomp profiles by default for historical reasons. You should enable it to ensure that the workloads have restricted actions available within the container.

Impact

If the default seccomp profile is too restrictive for you, you will need to create and manage your own seccomp profiles, which can be done using OpenShift Security Context Constraints and custom seccomp profiles.

Audit Procedure

In OpenShift 4, CRI-O is the supported runtime. CRI-O runs unconfined by default in order to meet CRI conformance criteria.

On Red Hat CoreOS, the default seccomp policy is associated with CRI-O and stored in /etc/crio/seccomp.json. The default profile is applied when the user asks for the RuntimeDefault profile via annotation to the pod and when the associated SCC allows use of the specified seccomp profile.

Use the following command to find all non-default pods that do not have a seccomp profile set:

oc get pods -A -o json | jq '.items[] | select( (.metadata.namespace | test("^kube*|^openshift*") | not) and .spec.securityContext.seccompProfile.type==null) | (.metadata.namespace + "/" + .metadata.name)'

The output will return a list of namespace pod pairs that do not have a seccomp profile set.

Remediation

For any non-privileged pods or containers that do not have seccomp profiles, consider using the RuntimeDefault or creating a custom seccomp profile specifically for the workload.

Please refer to the OpenShift documentation for working with custom seccomp profiles.

Default Value

By default, OpenShift applies the restricted-v2 SCC to all pods, which uses the RuntimeDefault seccomp profile.

References

1. https://docs.openshift.com/container-platform/latest/authentication/managing-security-context-constraints.html
2. https://github.com/kubernetes/kubernetes/issues/39845
3. https://github.com/kubernetes/kubernetes/pull/21790
4. https://github.com/kubernetes/community/blob/master/contributors/design-proposals/seccomp.md#examples
5. https://docs.docker.com/engine/security/seccomp/
6. https://docs.openshift.com/container-platform/latest/security/seccomp-profiles.html

CIS Controls

MITRE ATT&CK Mappings

Profile

Level 2 (Manual)