---
id: "CVE-2026-122321"
kind: "vulnerability"
aliases: ["CVE-2026-122321"]
title: "Kyverno: cached image checks let swapped tags bypass signature verification"
severity: "critical"
cvss: 9.1
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["container-images", "infrastructure", "kubernetes", "kyverno", "supply-chain"]
not_affected_if: ["no-verifyimages-policy", "patched-version"]
published_at: "2026-11-05T03:17:25+00:00"
first_seen_at: "2026-11-05T03:31:42+00:00"
updated_at: "2026-11-05T03:33:09+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-122321", "first_seen_at": "2026-11-05T03:31:42+00:00"}]
exploit_sources: []
---

# Kyverno: cached image checks let swapped tags bypass signature verification

Kyverno 1.18.0 before 1.19.2 caches image verification results by tag rather than by verified digest, so a cache hit skips signature and attestation checks. An attacker who can submit workloads and move a registry tag can get an unsigned image admitted to the cluster.

_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 deployment -n kyverno kyverno-admission-controller -o jsonpath='{.spec.template.spec.containers[0].image}'`
- Look for `verifyImages` rules in ClusterPolicy or Policy resources that use `mutateDigest`

## Fix

- Kyverno: move to `1.19.2` or later

## Timeline

- 2026-11-05T03:31:42+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-122321

## Documents

- [advisory] Vendor advisory: github.com https://github.com/kyverno/kyverno/security/advisories/GHSA-2r43-6962-xcw5
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/kyverno-1.18.0-before-1.19.2-verifyimages-cache-signature-verification-bypass

## From the sources

Kyverno 1.18.0 before 1.19.2 contains a signature verification bypass in verifyImages because cached verification results are keyed by the image reference string (such as a tag) rather than bound to the verified digest, so cache hits skip signature and attestation checks. An attacker who can submit workloads and move a registry tag can warm the cache with a signed image, repoint the tag, and have Kyverno admit the workload and use mutateDigest to pin the unverified digest.

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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_