Privileged execution

Tetragon also provides the ability to check process capabilities and kernel namespaces access.

This information would help us determine which process or Kubernetes pod has started or gained access to privileges or host namespaces that it should not have. This would help us answer questions like:

Which Kubernetes pods are running with CAP_SYS_ADMIN in my cluster?

Which Kubernetes pods have host network or pid namespace access in my cluster?

As a first step let’s enable visibility to capability and namespace changes via the configmap by setting enable-process-cred and enable-process-ns from false to true:

kubectl edit cm -n kube-system tetragon-config
# change "enable-process-cred" from "false" to "true"
# change "enable-process-ns" from "false" to "true"
# then save and exit

Restart the Tetragon daemonset:

kubectl rollout restart -n kube-system ds/tetragon

As a second step, let’s start monitoring the Security Observability events from the privileged test-pod workload:

kubectl logs -n kube-system -l app.kubernetes.io/name=tetragon -c export-stdout -f | tetra getevents --namespace default --pod test-pod

In another terminal let’s apply the privileged PodSpec:

kubectl apply -f https://raw.githubusercontent.com/cilium/tetragon/main/testdata/specs/testpod.yaml

If you observe the output in the first terminal, you can see the container start with CAP_SYS_ADMIN:

🚀 process default/test-pod /bin/sleep 365d                🛑 CAP_SYS_ADMIN
🚀 process default/test-pod /usr/bin/jq -r .bundle         🛑 CAP_SYS_ADMIN
🚀 process default/test-pod /usr/bin/cp /kind/product_name /kind/product_uuid /run/containerd/io.containerd.runtime.v2.task/k8s.io/7c7e513cd4d506417bc9d97dd9af670d94d9e84161c8c8 fdc9fa3a678289a59/rootfs/ 🛑 CAP_SYS_ADMIN