CVE-2026-122318
Full vulnerability record from the local CVENow database.
Description
Kyverno before 1.19.2 contains an authentication bypass in matchCertificateData that skips verifyImages subject and subjectRegExp checks when the signing certificate has no Subject Alternative Name. Attackers holding a leaf certificate from a configured private trust root can omit the SAN, set the expected Fulcio issuer OID, and sign malicious images that are admitted despite signer pinning.
Severity
HIGH
CVSS score
7.2
(v4.0)
Vulnerability status
Received
Source identifier
Published
2026-11-05 03:17:24.523000
Last modified
2026-11-05 03:17:24.523000
View original CVE JSON
{
"id": "CVE-2026-122318",
"sourceIdentifier": "[email protected]",
"published": "2026-11-05T03:17:24.523",
"lastModified": "2026-11-05T03:17:24.523",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Kyverno before 1.19.2 contains an authentication bypass in matchCertificateData that skips verifyImages subject and subjectRegExp checks when the signing certificate has no Subject Alternative Name. Attackers holding a leaf certificate from a configured private trust root can omit the SAN, set the expected Fulcio issuer OID, and sign malicious images that are admitted despite signer pinning."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "kyverno",
"product": "kyverno",
"defaultStatus": "unaffected",
"packageURL": "pkg:golang/github.com/kyverno/kyverno",
"versions": [
{
"version": "0",
"lessThan": "1.19.2",
"versionType": "semver",
"status": "affected"
},
{
"version": "1.19.2",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV40": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "4.0",
"vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:H/VA:L/SC:L/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"baseScore": 7.2,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"attackRequirements": "PRESENT",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "LOW",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "LOW",
"subConfidentialityImpact": "LOW",
"subIntegrityImpact": "HIGH",
"subAvailabilityImpact": "LOW",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
],
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:H/A:L",
"baseScore": 7.7,
"baseSeverity": "HIGH",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "CHANGED",
"confidentialityImpact": "LOW",
"integrityImpact": "HIGH",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 1.8,
"impactScore": 5.3
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-295"
}
]
}
],
"references": [
{
"url": "https://github.com/kyverno/kyverno/security/advisories/GHSA-fcfr-fr8g-qjqv",
"source": "[email protected]"
},
{
"url": "https://www.vulncheck.com/advisories/kyverno-before-1.19.2-cosign-identity-check-bypass-via-empty-san-certificates",
"source": "[email protected]"
}
]
}