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.
CVSS Details
- CVSS 4.0 Base Score: 8.3 (HIGH)
- CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
- CVSS 3.1 Base Score: 7.7
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N)
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub