Disallow Capabilities

 1apiVersion: kyverno.io/v1
 2kind: ClusterPolicy
 3metadata:
 4  name: disallow-capabilities
 5  annotations:
 6    policies.kyverno.io/title: Disallow Capabilities
 7    policies.kyverno.io/category: Pod Security Standards (Baseline)
 8    policies.kyverno.io/severity: medium
 9    kyverno.io/kyverno-version: 1.6.0
10    policies.kyverno.io/minversion: 1.6.0
11    kyverno.io/kubernetes-version: "1.22-1.23"
12    policies.kyverno.io/subject: Pod
13    policies.kyverno.io/description: >-
14      Adding capabilities beyond those listed in the policy must be disallowed.      
15spec:
16  validationFailureAction: audit
17  background: true
18  rules:
19    - name: adding-capabilities
20      match:
21        any:
22        - resources:
23            kinds:
24              - Pod
25      preconditions:
26        all:
27        - key: "{{ request.operation || 'BACKGROUND' }}"
28          operator: NotEquals
29          value: DELETE
30      validate:
31        message: >-
32          Any capabilities added beyond the allowed list (AUDIT_WRITE, CHOWN, DAC_OVERRIDE, FOWNER,
33          FSETID, KILL, MKNOD, NET_BIND_SERVICE, SETFCAP, SETGID, SETPCAP, SETUID, SYS_CHROOT)
34          are disallowed.          
35        deny:
36          conditions:
37            all:
38            - key: "{{ request.object.spec.[ephemeralContainers, initContainers, containers][].securityContext.capabilities.add[] }}"
39              operator: AnyNotIn
40              value:
41              - AUDIT_WRITE
42              - CHOWN
43              - DAC_OVERRIDE
44              - FOWNER
45              - FSETID
46              - KILL
47              - MKNOD
48              - NET_BIND_SERVICE
49              - SETFCAP
50              - SETGID
51              - SETPCAP
52              - SETUID
53              - SYS_CHROOT