CVE-2026-100706: kyverno before 1.19.1 Privilege Escalation via Policy apiCall urlPath
kyverno before 1.19.1 fails to properly validate URL-encoded path segments in Policy apiCall urlPath, allowing namespace tenants to bypass the per-namespace clamp and create objects in other namespaces as the admission-controller ServiceAccount. Attackers can exploit this by using percent-encoded directory traversal sequences to create MutatingWebhookConfiguration objects cluster-wide or PolicyException objects in the kyverno namespace, enabling privilege escalation to cluster admin.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
kyvernoto a version that resolves this vulnerability.Fixed in 1.19.1
Event History
Frequently Asked Questions
Who can exploit this issue?
A namespace tenant with permissions to create or use a Kyverno Policy containing an apiCall urlPath can exploit the flaw. The attack does not require user interaction and can be performed remotely.
What access can an attacker obtain?
By bypassing the per-namespace path clamp, an attacker can cause objects to be created as Kyverno's admission-controller ServiceAccount. They can create cluster-wide MutatingWebhookConfiguration objects or PolicyException objects in the kyverno namespace, which can lead to cluster-admin privilege escalation.
Are installations running Kyverno 1.19.1 or later affected?
The affected versions are stated as Kyverno before 1.19.1. This issue concerns insufficient validation of URL-encoded path segments in Policy apiCall urlPath values.