CVE-2026-122308
Description
A flaw was found in Kyverno. An authorization bypass vulnerability in the Generation Handler allows authenticated users with resource creation or update privileges to trigger automated generation policies by spoofing internal system labels. By applying crafted labels to resources such as configuration maps, an attacker can clone sensitive secrets from restricted namespaces into their own namespace, resulting in unauthorized information disclosure.
Statement
This vulnerability is rated Important because an authenticated cluster user with restricted privileges can bypass multi-tenancy boundaries and extract sensitive data across namespaces. In environments running Kyverno where synchronized generation rules are deployed, users who only possess permissions to create or modify local resources can spoof internal metadata tags. Consequently, the controller mistakenly propagates protected assets into unauthorized namespaces, breaking container platform tenant isolation.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
--- CME Mitigation Guidance (2026-11-06) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to validate and reject user-submitted resources containing internal generate.kyverno.io or Kyverno management labels at the admission webhook boundary before processing by the Generation Handler: upgrade to Kyverno 1.19.2 (or the corresponding fixed Red Hat builds), which validate and prevent unauthorized users from submitting internal generate.kyverno.io labels and Kyverno management metadata during admission webhook processing, closing all 2 injection vectors (spoofing internal generate.kyverno.io policy, rule, and trigger labels, spoofing the app.kubernetes.io/managed-by kyverno label on user-created resources). Until patched, this is a concern on Kubernetes clusters running Kyverno with synchronized generate policies where authenticated users can create or update resources, so Audit and restrict namespace-level create and update permissions for resources like ConfigMaps, and monitor for unexpected generate.kyverno.io metadata and cross-namespace Secret creation. As a compensating measure, Configure Kubernetes API server audit logging to detect the creation of ConfigMaps carrying spoofed internal labels and subsequent unauthorized access to cloned Secrets across namespaces. These controls limit blast radius and contain exploitation, but they do not fix the underlying internal label spoofing authorization bypass — apply the upstream patch to fully remediate.
Highest-impact CME: CME-711 Admission Controller Policy Enforcement (OPA/Gatekeeper/Kyverno) (high)
Understanding the Weakness (CWE)
Confidentiality,Access Control,Availability
Technical Impact: Bypass Protection Mechanism; Gain Privileges or Assume Identity; Varies by Context
When security decisions such as authentication and authorization are made based on the values of these inputs, attackers can bypass the security of the product to access whatever is being protected. An attacker could change these inputs using customized clients or other attacks. This change might not be detected. The consequences will depend on the associated functionality, but they can range from granting additional privileges to untrusted users to bypassing important security checks. Ultimately, this weakness may lead to exposure or modification of sensitive data, system crash, or execution of arbitrary code.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
