CVE-2023-34091

Vulnerability Description

Kyverno is a policy engine designed for Kubernetes. In versions of Kyverno prior to 1.10.0, resources which have the `deletionTimestamp` field defined can bypass validate, generate, or mutate-existing policies, even in cases where the `validationFailureAction` field is set to `Enforce`. This situation occurs as resources pending deletion were being consciously exempted by Kyverno, as a way to reduce processing load as policies are typically not applied to objects which are being deleted. However, this could potentially result in allowing a malicious user to leverage the Kubernetes finalizers feature by setting a finalizer which causes the Kubernetes API server to set the `deletionTimestamp` and then not completing the delete operation as a way to explicitly to bypass a Kyverno policy. Note that this is not applicable to Kubernetes Pods but, as an example, a Kubernetes Service resource can be manipulated using an indefinite finalizer to bypass policies. This is resolved in Kyverno 1.10.0. There is no known workaround.

CVSS Score

Affected Products

Related Weaknesses (CWE)

References

• https://github.com/kyverno/kyverno/releases/tag/v1.10.0Release Notes
• https://github.com/kyverno/kyverno/security/advisories/GHSA-hq4m-4948-64ccVendor Advisory
• https://github.com/kyverno/kyverno/releases/tag/v1.10.0Release Notes
• https://github.com/kyverno/kyverno/security/advisories/GHSA-hq4m-4948-64ccVendor Advisory