Abhinav Sinha
124e5276d4
- Split `scenarios/scenarios.json` into individual JSON files under `scenarios/data/` named `<scenario-id>.json` - Split `scenarios/bundles.json` into individual JSON files under `scenarios/bundles/` named `<bundle-id>.json` - Updated `backend/server.js` to dynamically load scenario and bundle files from their respective directories - Updated documentation in `scenarios/SCHEMA.md` and `README.md` to reflect the new repository layout and contributor workflow Signed-off-by: Abhinav Sinha <[email protected]>
40 lines
2.1 KiB
JSON
40 lines
2.1 KiB
JSON
{
|
|
"id": "cks-mcq-sandboxing",
|
|
"title": "Container Runtime Sandboxing",
|
|
"category": "System Hardening",
|
|
"difficulty": "Hard",
|
|
"type": "mcq",
|
|
"weight": 3,
|
|
"description": "## Container Runtime Sandboxing\n\nA security team wants to run untrusted workloads with stronger isolation than the standard `runc` runtime — specifically, they want each container's system calls to be intercepted by a user-space kernel rather than reaching the host kernel directly.\n\nWhich solution achieves this, and how is it configured in Kubernetes?",
|
|
"options": [
|
|
{
|
|
"id": "a",
|
|
"text": "Seccomp with `RuntimeDefault` — restricts which syscalls are allowed via a BPF filter, but syscalls still reach the host kernel"
|
|
},
|
|
{
|
|
"id": "b",
|
|
"text": "AppArmor with a `deny` profile — enforces path-based MAC policies but does not intercept syscalls"
|
|
},
|
|
{
|
|
"id": "c",
|
|
"text": "gVisor (`runsc`) via a `RuntimeClass` — intercepts all syscalls in user-space with its own kernel implementation, isolating the host kernel from the container"
|
|
},
|
|
{
|
|
"id": "d",
|
|
"text": "A `PodDisruptionBudget` — prevents pod disruptions and provides workload isolation"
|
|
}
|
|
],
|
|
"correct_option": "c",
|
|
"explanation": "**gVisor** (`runsc`) is a user-space kernel from Google that intercepts all container system calls before they reach the host kernel, providing strong isolation. In Kubernetes it is configured via a **RuntimeClass** resource and referenced in a pod with `spec.runtimeClassName`. Kata Containers is a similar alternative using lightweight VMs. Seccomp filters syscalls but they still hit the host kernel. AppArmor enforces file-access policies, not syscall interception.",
|
|
"hints": [
|
|
{
|
|
"title": "RuntimeClass and runtimeClassName",
|
|
"body": "Create a `RuntimeClass` that maps a name to the container runtime handler (e.g., `handler: runsc`). Reference it in a pod with `spec.runtimeClassName: <name>`.",
|
|
"command": "kubectl explain runtimeclass\nkubectl explain pod.spec.runtimeClassName"
|
|
}
|
|
],
|
|
"setup_commands": [],
|
|
"default_namespace": "default",
|
|
"teardown_commands": []
|
|
}
|