Kyverno Cross-Namespace Privilege Escalation via Policy apiCall

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.9 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-22039: 0.58% estimated exploitation activity in the next 30 days; percentile 47.65 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A critical authorization boundary bypass in namespaced Kyverno Policy apiCall. The resolved urlPath is executed using the Kyverno admission controller ServiceAccount, with no enforcement that the request is limited to the policy’s namespace. As a result, any authenticated user with permission to create a namespaced Policy can cause Kyverno to perform Kubernetes API requests using Kyverno’s admission controller identity, targeting any API path allowed by that ServiceAccount’s RBAC. This breaks namespace isolation by enabling cross-namespace reads (for example, ConfigMaps and, where permitted, Secrets) and allows cluster-scoped or cross-namespace writes (for example, creating ClusterPolicies) by controlling the urlPath through context variable substitution. Details The vulnerability exists in how Kyverno handles apiCall context entries. The code substitutes variables into the URLPath field without sanitizing the output or validating that the resulting path is authorized for the…

Published by the source

27 Jan 2026, 18:01 UTC

Last modified by the source

29 Jan 2026, 03:31 UTC

Source last checked

26 Oct 2026, 15:14 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8p9x-46gm-qfx2

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# Patch Next advisory brief: CVE-2026-22039

Advisory: Kyverno Cross-Namespace Privilege Escalation via Policy apiCall
IDs: CVE-2026-22039, GHSA-8p9x-46gm-qfx2
Record: https://patchnext.com/advisories/cve-2026-22039 (revision 1, source checked 26 Oct 2026, 15:14 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/kyverno/kyverno 1.16.3, 1.15.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/kyverno/kyverno: affected < 1.15.3; >= 1.16.0-rc.1, < 1.16.3; fixed in 1.15.3, 1.16.3

## Suggested inspection (read-only)
- Go github.com/kyverno/kyverno: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/kyverno/kyverno.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-8p9x-46gm-qfx2 (GitHub-reviewed advisory GHSA-8p9x-46gm-qfx2 lists affected ranges: Go github.com/kyverno/kyverno >=0 =1.16.0-rc.1 <1.16.3)

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