CVE-2026-63121

MEDIUM CVSS 3.1: 6.3 EPSS 0.19%
Updated Oct 31, 2026
Kubernetes
Parameter Value
CVSS 6.3 (MEDIUM)
Affected Versions before 2.1.2
Fixed In 2.1.2
Type CWE-178
Vendor Kubernetes
Public PoC No

Kubewarden policies is a collection of WebAssembly policies for securing and governing Kubernetes clusters. For versions provisionally classified as affected before 2.1.2, `trusted-repos-policy` compares an image's `registry` hostname against `reject lists` and `allow lists` case-sensitively even though `registry` DNS names are case-insensitive. An image with an uppercase or mixed-case `registry` hostname can miss a rejection rule for the equivalent lowercase host, so the admission policy accepts a resource whose container runtime pulls the same prohibited image.

Only reject-list configurations have this bypass: allow-list configurations fail closed by over-denying differently cased hostnames. The security consequences depend on the configured rejection policy and deployment environment. This issue is fixed in version 2.1.2.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required

Impact Assessment

Confidentiality
Low
Partial data leak
Integrity
Low
Partial data modification
Availability
Low
Partial disruption

CVSS Vector v3.1

Weakness Type (CWE)