KubernetesOverview
The ability to create pods in a namespace can provide a number of opportunities for privilege escalation, such as assigning privileged service accounts to these pods or mounting hostPaths with access to sensitive data (unless Pod Security Policies are implemented to restrict this access)
As such, access to create new pods should be restricted to the smallest possible group of users.
Rationale
The ability to create pods in a cluster opens up possibilities for privilege escalation and should be restricted, where possible.
Impact
Care should be taken not to remove access to pods to system components which require this for their operation.
Remediation guidance
Where possible, remove create access to pod objects in the cluster.
References
-
https://workbench.cisecurity.org/sections/1126661/recommendations/1838592
-
https://kubernetes.io/docs/reference/access-authn-authz/rbac/
Multiple Remediation Paths
SERVICE-WIDE (RECOMMENDED when many resources are affected): Apply organization/tenant-level guardrails and baseline policies for the entire platform.
ASSET-LEVEL: Fix only the affected resources identified by this control.
PREVENTIVE: Add preventive policy checks to CI/CD and periodic posture scans.
References for Service-Wide Patterns
- Platform policy/governance and preventive control patterns should be applied tenant-wide where supported.
Query logic
These are the stored checks tied to this control.
Kubernetes RoleBindings to Roles that can create pods
Connectors
Covered asset types
Expected check: eq []
{
roles(
where: {
AND: [
{
rules_SOME: {
AND: [
{
OR: [
{ verbs_INCLUDES: "create" }
{ verbs_INCLUDES: "*" }
]
}
{
OR: [
{ resources_INCLUDES: "pods" }
{ resources_INCLUDES: "*" }
]
}
{ OR: [{ apiGroup_INCLUDES: "" }, { apiGroup_INCLUDES: "*" }] }
]
}
},
{bindings_SOME: {idFromProvider_NOT: ""}}
]
}
) {
bindings {
...AssetFragment
}
}
}
Kubernetes RoleBindings to ClusterRoles that can create pods
Connectors
Covered asset types
Expected check: eq []
{
clusterRoles(
where: {
AND: [
{
rules_SOME: {
AND: [
{
OR: [
{ verbs_INCLUDES: "create" }
{ verbs_INCLUDES: "*" }
]
}
{
OR: [
{ resources_INCLUDES: "pods" }
{ resources_INCLUDES: "*" }
]
}
{ OR: [{ apiGroup_INCLUDES: "" }, { apiGroup_INCLUDES: "*" }] }
]
}
},
{roleBindings_SOME: {idFromProvider_NOT: ""}}
]
}
) {
roleBindings {
...AssetFragment
}
}
}
Kubernetes RoleBindings to ClusterRoles that can create pods
Connectors
Covered asset types
Expected check: eq []
{
clusterRoles(
where: {
AND: [
{
rules_SOME: {
AND: [
{
OR: [
{ verbs_INCLUDES: "create" }
{ verbs_INCLUDES: "*" }
]
}
{
OR: [
{ resources_INCLUDES: "pods" }
{ resources_INCLUDES: "*" }
]
}
{ OR: [{ apiGroup_INCLUDES: "" }, { apiGroup_INCLUDES: "*" }] }
]
}
},
{clusterRoleBindings_SOME: {idFromProvider_NOT: ""}}
]
}
) {
clusterRoleBindings {
...AssetFragment
}
}
}
