CVE-2026-63121
Kubewarden trusted-repos-policy: uppercase registry host bypasses registry/image deny rules
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 profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
6.3
Kubewarden trusted-repos-policy: uppercase registry host bypasses registry/image deny rules
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.
- Record
CVE-2026-63121- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-178
- Updated
- 2026-11-05
EUVDEUVD-2026-114566
6.3
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.
- Record
EUVD-2026-114566- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Updated
- 2026-11-05
NVD
6.3
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.
- Record
CVE-2026-63121- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-178
- Updated
- 2026-11-05
OSV
6.3
Kubewarden trusted-repos-policy: uppercase registry host bypasses registry/image deny rules
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.
- Record
CVE-2026-63121- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L - Weakness
- CWE-178
- Updated
- 2026-11-05
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | NVD, OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-63121 is a medium vulnerability (CVSS 6.3) in Hulumi Policies, published October 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.19%, the 9th percentile. No source names a fixed version.
References
github.com/kubewarden/policies/security/advisories/GHSA-8p62-9vh2-272p
github.com/kubewarden/policies/commit/bc5597fcbbb0bc464b714ca7ff645c9743dea41b
github.com/kubewarden/policies/tree/trusted-repos-policy/v2.1.2
github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63121.json
nvd.nist.gov/vuln/detail/CVE-2026-63121