by Kastro
Paper/Archive/CVE-2026-41323

CVE-2026-41323

kyverno kyverno — Kyverno: ServiceAccount token leaked to external servers via apiCall service URL

EPSS 0.6%public exploitCVSS 9.1
critical.is priorityof 100
47
CVSS 9.1 (NVD)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 46.6.466 × 209.3Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

Kyverno is a policy engine designed for cloud native platform engineering teams. Prior to versions 1.18.0-rc1, 1.17.2-rc1, and 1.16.4, Kyverno's apiCall feature in ClusterPolicy automatically attaches the admission controller's ServiceAccount token to outgoing HTTP requests. The service URL has no validation — it can point anywhere, including attacker-controlled servers. Since the admission controller SA has permissions to patch webhook configurations, a stolen token leads to full cluster compromise. Versions 1.18.0-rc1, 1.17.2-rc1, and 1.16.4 patch the issue.

Affected

ProductAffectedFixed inSource
kyverno< 1.16.4–CNA
kyverno>= 1.17.0-rc1, < 1.17.2-rc1–CNA

Scores by source

NVD9.1CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
GitHub_M (CNA)8.1CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: total

References

exploitgithub.com/kyverno/kyverno/security/advisories/GHSA-f9g8-6ppc-pqq4refgithub.com/kyverno/kyverno/commit/bc4f91c4801b1eaa2edc0a14e2f1b0af8cf0c1f5refgithub.com/kyverno/kyverno/commit/c2eab00033e635bda4e4efb58c1b472b41728bb6refgithub.com/kyverno/kyverno/commit/f70e8ac1e7acd2e3844f9553e4a884f07f953de0