---
id: "CVE-2026-122316"
kind: "vulnerability"
aliases: ["CVE-2026-122316"]
title: "Kyverno: namespaced tenants can modify resources outside their namespace"
severity: "high"
cvss: 8.5
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["kubernetes", "kyverno", "multi-tenant", "runtime"]
not_affected_if: ["kyverno-1.19.2-or-later", "single-tenant-cluster"]
published_at: "2026-11-05T03:17:24+00:00"
first_seen_at: "2026-11-05T03:31:42+00:00"
updated_at: "2026-11-05T03:33:16+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-122316", "first_seen_at": "2026-11-05T03:31:42+00:00"}]
exploit_sources: []
---

# Kyverno: namespaced tenants can modify resources outside their namespace

Kyverno's mutate-existing background processor lacks an authorization check, so a namespace tenant can create a NamespacedMutatingPolicy that changes objects in other namespaces. The attack makes the background-controller service account strip Pod Security labels cluster-wide.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Kyverno version with `kubectl get deploy -n kyverno -o jsonpath='{.items[*].spec.template.spec.containers[*].image}'`
- List NamespacedMutatingPolicy objects with `kubectl get namespacedmutatingpolicies -A` and review which tenants can create them

## Fix

- Kyverno: move to `1.19.2` or later (the sources state fixed versions from 1.17.0 before 1.19.2)

## Timeline

- 2026-11-05T03:31:42+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-122316

## Documents

- [advisory] Vendor advisory: github.com https://github.com/kyverno/kyverno/security/advisories/GHSA-vm98-8c25-h274
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/kyverno-1.17.0-before-1.19.2-cross-namespace-write-via-namespacedmutatingpolicy-mutateexisting

## From the sources

Kyverno from 1.17.0 before 1.19.2 contains a missing authorization vulnerability in the mutate-existing background processor that allows namespaced tenants to modify resources outside their namespace. Attackers can create a NamespacedMutatingPolicy targeting Namespace objects or victim-namespace resources via CEL expressions, making the background-controller ServiceAccount strip Pod Security labels cluster-wide.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_