Container using read-write root filesystem

No violationsstackroxmediumdeploy

Alert on deployments with containers with read-write root filesystem

Rationale: Containers running with read-write root filesystem represent greater post-exploitation risk by allowing an attacker to modify important files in the container.
Remediation: Use a read-only root filesystem, and use volume mounts to allow writes to specific sub-directories depending on your application's needs.

CategoriesDocker CISPrivileges

Compliance mappingsView coverage →

CIS Kubernetes Benchmark v1.8: 5.7.2
DORA EU 2022/2554: Art. 9.2
ISO/IEC 27001 2022: A.8.2A.8.9
NIST SP 800-53 rev. 5: AC-6CM-2CM-6
PCI DSS 4.0: 2.2.12.2.67.2.1
SOC 2 2017 TSC: CC6.1

Generated artifacts

3 of 5 targets supported

container-using-read-write-root-filesystem.yaml

apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: container-using-read-write-root-filesystem
  annotations:
    policies.kyverno.io/title: Container using read-write root filesystem
    policies.kyverno.io/category: Docker CIS, Privileges
    policies.kyverno.io/severity: medium
    policies.kyverno.io/description: Alert on deployments with containers with read-write root filesystem
    policies.kyverno.io/remediation: Use a read-only root filesystem, and use volume mounts to allow writes to specific sub-directories depending on your application's needs.
    policies.kyverno.io/rationale: Containers running with read-write root filesystem represent greater post-exploitation risk by allowing an attacker to modify important files in the container.
    policies.io/source: stackrox
    policies.io/source-id: 8ac93556-4ad4-4220-a275-3f518db0ceb9
spec:
  validationFailureAction: Audit
  background: true
  rules:
    - name: container-using-read-write-root-filesystem
      match:
        any:
          - resources:
              kinds:
                - Pod
      validate:
        message: 'Policy "Container using read-write root filesystem" violated: Alert on deployments with containers with read-write root filesystem'
        deny:
          conditions:
            all:
              - key: "{{ request.object.spec.containers[].securityContext.readOnlyRootFilesystem || `[]` }}"
                operator: AnyNotIn
                value:
                  - true
      exclude:
        any:
          - resources:
              namespaces:
                - kube-system
          - resources:
              namespaces:
                - istio-system
          - resources:
              namespaces:
                - openshift-node
          - resources:
              namespaces:
                - openshift-sdn

IR (canonical)

{
  "id": "8ac93556-4ad4-4220-a275-3f518db0ceb9",
  "name": "Container using read-write root filesystem",
  "description": "Alert on deployments with containers with read-write root filesystem",
  "rationale": "Containers running with read-write root filesystem represent greater post-exploitation risk by allowing an attacker to modify important files in the container.",
  "remediation": "Use a read-only root filesystem, and use volume mounts to allow writes to specific sub-directories depending on your application's needs.",
  "severity": "medium",
  "categories": [
    "Docker CIS",
    "Privileges"
  ],
  "lifecycle": [
    "deploy"
  ],
  "eventSource": "none",
  "scope": [],
  "exclusions": [
    {
      "name": "Don't alert on kube-system namespace",
      "namespace": "kube-system"
    },
    {
      "name": "Don't alert on istio-system namespace",
      "namespace": "istio-system"
    },
    {
      "name": "Don't alert on openshift-node namespace",
      "namespace": "openshift-node"
    },
    {
      "name": "Don't alert on openshift-sdn namespace",
      "namespace": "openshift-sdn"
    }
  ],
  "enforcement": {
    "failBuild": false
  },
  "expression": {
    "op": "criterion",
    "field": "read-only-root-fs",
    "values": [
      "false"
    ],
    "valuesOp": "or",
    "negate": false
  },
  "disabled": true
}

Original StackRox JSON

{
  "id": "8ac93556-4ad4-4220-a275-3f518db0ceb9",
  "name": "Container using read-write root filesystem",
  "description": "Alert on deployments with containers with read-write root filesystem",
  "rationale": "Containers running with read-write root filesystem represent greater post-exploitation risk by allowing an attacker to modify important files in the container.",
  "remediation": "Use a read-only root filesystem, and use volume mounts to allow writes to specific sub-directories depending on your application's needs.",
  "disabled": true,
  "categories": [
    "Docker CIS",
    "Privileges"
  ],
  "lifecycleStages": [
    "DEPLOY"
  ],
  "eventSource": "NOT_APPLICABLE",
  "exclusions": [
    {
      "name": "Don't alert on kube-system namespace",
      "deployment": {
        "name": "",
        "scope": {
          "cluster": "",
          "namespace": "kube-system",
          "label": null
        }
      },
      "image": null
    },
    {
      "name": "Don't alert on istio-system namespace",
      "deployment": {
        "name": "",
        "scope": {
          "cluster": "",
          "namespace": "istio-system",
          "label": null
        }
      },
      "image": null
    },
    {
      "name": "Don't alert on openshift-node namespace",
      "deployment": {
        "name": "",
        "scope": {
          "cluster": "",
          "namespace": "openshift-node",
          "label": null
        }
      },
      "image": null
    },
    {
      "name": "Don't alert on openshift-sdn namespace",
      "deployment": {
        "name": "",
        "scope": {
          "cluster": "",
          "namespace": "openshift-sdn",
          "label": null
        }
      },
      "image": null
    }
  ],
  "scope": [],
  "severity": "MEDIUM_SEVERITY",
  "enforcementActions": [],
  "policySections": [
    {
      "sectionName": "",
      "policyGroups": [
        {
          "fieldName": "Read-Only Root Filesystem",
          "booleanOperator": "OR",
          "negate": false,
          "values": [
            {
              "value": "false"
            }
          ]
        }
      ]
    }
  ],
  "notifiers": [],
  "lastUpdated": null,
  "SORTName": "",
  "SORTLifecycleStage": "",
  "SORTEnforcement": false,
  "policyVersion": "1.1",
  "mitreAttackVectors": [],
  "criteriaLocked": true,
  "mitreVectorsLocked": true,
  "isDefault": true,
  "source": "IMPERATIVE"
}