CVE-2026-54523

CRITICALPre-NVD 9.69.6—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.6 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 67% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
9.6EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.6Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Kyverno is a policy engine designed for cloud native platform engineering teams. From 1.18.0 until 1.18.2, the NamespacedMutatingPolicy CEL compiler exposes the generator library to matchConditions, allowing a namespace-scoped policy to invoke generator.apply(namespace, resources) with an arbitrary target namespace. The validation in pkg/cel/policies/mpol/validate.go checks that the policy compiles but does not enforce namespace scope, and GenerateResources in pkg/cel/libs/context.go does not reject the cross-namespace target. A user who can create NamespacedMutatingPolicy objects in one namespace can cause the admission controller, operating with cluster-wide privileges, to create ConfigMaps, NetworkPolicies, Secrets, RoleBindings, and other resources in another namespace, enabling unauthorized modification and potential privilege escalation. This issue is fixed in version 1.18.2.

CVSS v3
9.6
EG Score
9.6(medium)
EG Risk
48(Track)
EG Risk 48/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity96% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
33%
KEV
Not listed

Published

August 26, 2026

Last Modified

August 26, 2026

Advisory Details (6)

Auto-updated Aug 28, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_pr, github_release.
github Patch Available🟡 PoC Available

NamespacedMutatingPolicy generator.apply() namespace argument unvalidated in v1.18.1 - allows cross-namespace resource generation via admission controller · Advisory · kyverno/kyverno · GitHub

https://github.com/kyverno/kyverno/security/advisories/GHSA-79gf-7frw-68m9
github_commit

commit 657393744144 (kyverno/sdk)

Fix landed in kyverno/sdk commit 657393744144 — awaiting tagged release

https://github.com/kyverno/sdk/commit/6573937441443e1ba5af9fbb28d5c0f20297f9df
github_release Patch Available

v1.18.2

Patch available: kyverno/kyverno v1.18.2

https://github.com/kyverno/kyverno/releases/tag/v1.18.2
github_pr

fix(gpol,mpol): enforce namespace boundary in generator.apply() (backport GHSA-79gf-7frw-68m9 to release-1.18)

Fix merged in kyverno/kyverno PR #16238 on 2026-06-05 — awaiting tagged release

https://github.com/kyverno/kyverno/pull/16238
github_commit

commit 5164bcdeda5b (kyverno/kyverno)

Fix landed in kyverno/kyverno commit 5164bcdeda5b — awaiting tagged release

https://github.com/kyverno/kyverno/commit/5164bcdeda5b57678bc2d7a03ecc2cbb02982dae
github_commit

commit 0919553c0ea1 (kyverno/kyverno)

Fix landed in kyverno/kyverno commit 0919553c0ea1 — awaiting tagged release

https://github.com/kyverno/kyverno/commit/0919553c0ea1904f8d891280c92018da97946a06

Vendor Advisories for CVE-2026-54523(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 9× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-30 02:04 UTCEG score recompute
  2. 2026-08-30 01:22 UTCEPSS rescore
  3. 2026-08-28 23:58 UTCEG score recompute
  4. 2026-08-28 21:41 UTCEPSS rescore
  5. 2026-08-27 18:27 UTCEG score recompute
  6. 2026-08-27 14:25 UTCEPSS rescore
  7. 2026-08-26 15:49 UTCEG score recompute
  8. 2026-08-26 14:23 UTCEG score recompute
  9. 2026-08-26 14:22 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-54523?
CVE-2026-54523 is a critical vulnerability published on August 26, 2026. Kyverno is a policy engine designed for cloud native platform engineering teams. From 1.18.0 until 1.18.2, the NamespacedMutatingPolicy CEL compiler exposes the generator library to matchConditions, allowing a namespace-scoped policy to invoke generator.apply(namespace, resources) with an arbitrary…
When was CVE-2026-54523 disclosed?
CVE-2026-54523 was first published in the National Vulnerability Database on August 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-54523 actively exploited?
CVE-2026-54523 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 66.9% of all scored CVEs.
What is the CVSS score of CVE-2026-54523?
CVE-2026-54523 has a CVSS v3 base score of 9.6 (NVD).
How do I remediate CVE-2026-54523?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-54523, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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