SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2023-34091

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`.

MEDIUM 6.5EPSS 0.50%

Does this matter?

Lower severity and a low EPSS score (0.50%). Track it; it rarely justifies an emergency change on its own.

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 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
EPSS
0.50% probability · 41th percentile
CISA KEV
Not listed
Weakness
CWE-285
Affected
nirmata/kyverno
Source
security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.