Kyverno is a policy engine for Kubernetes. In versions 1.14.0 through 1.19.0, the ImageValidatingPolicy (policies.kyverno.io/v1beta1) evaluator never reads the spec.images and spec.allowedValues fields of a PolicyException. Any PolicyException whose policyRefs and matchConditions match a resource causes image signature verification to be skipped for the entire resource rather than only for the listed images or values, so an exception intended to exempt a single trusted image exempts every image on the matched resource(s). As a result, unsigned or untrusted images can be admitted to the cluster without signature verification. This differs from ValidatingPolicy, GeneratingPolicy, and MutatingPolicy, which treat the same field as a partial exemption. The issue is fixed in version 1.19.1.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Network (N)
|
Exploit possible à distance via réseau (HTTP, API, etc.) |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
High (H)
|
Modification totale des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
None (N)
|
Aucune interruption de service |
Kyverno before 1.19.1 ImageValidatingPolicy Exception Bypass