CVE-2026-100703: Kyverno before 1.19.1 Cross-Namespace Data Access via globalcontext.Lib

Severity: high (CVSS 7.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-26 · updated 2026-09-28
Weakness: CWE-200

Description

Kyverno 1.16.0 through 1.19.0 registers the globalcontext.Lib CEL library in its policy environment without confining it to the policy's namespace, unlike the sibling libraries (resource.Lib, http.Lib, configMap loader) which are handed the policy namespace. A tenant who can create a namespaced policy (e.g. NamespacedValidatingPolicy, and likewise the namespaced mutating, deleting, generating, and image-validating policy kinds) in their own namespace can call globalContext.get("<entry>", "") and receive the full cached contents of a cluster-scoped GlobalContextEntry, including data cached from namespaces the tenant has no RBAC permission to read. No admission validation rejects such calls. Fixed in 1.19.1.

Affected products

kyverno: from 1.16.0 before 1.19.1 — fixed in 1.19.1

How to fix

Upgrade to a fixed version: kyverno 1.19.1. Check the vendor advisory for mitigations.

References

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