Kyverno identity check bypass for certificates without SAN
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- Present
- Impact type
- Spoofing
- Confidentiality · integrity · availability
- Low · High · Low
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-295.
Summary
Kyverno before 1.19.2 contains an authentication bypass in matchCertificateData. When the signing certificate has no Subject Alternative Name, the subject checks are skipped due to improper certificate validation (CWE-295). An attacker holding a leaf certificate from a configured private trust root can sign malicious images that Kyverno admits despite signer pinning.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
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.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Update Kyverno to version 1.19.2, which fixes the flaw.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA kyverno (kyverno) Fixed in 1.19.2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
kyverno 1.19.2
21 records Highest priority Priority MEDIUM 6 MEDIUM, 15 LOW
Other records, highest priority first
- TI-2026-85289 Kyverno path traversal in namespaced CEL policies reaches cluster objectsPriority MEDIUM 41
- TI-2026-85282 Authorization bypass in Kyverno lets namespace admins read SecretsPriority MEDIUM 41
- TI-2026-85291 Privilege escalation in Kyverno lets tenants mutate other namespacesPriority MEDIUM 40
Vendor assessments
Timeline
- 2026-11-05 Threatist record created from CVE-2026-122318
- 2026-11-05 Alias added: GHSA-p8fx-8mgf-mvw3
- 2026-11-06 Priority changed: MEDIUM → LOW
- 2026-11-06 Affected versions changed · Red Hat
- 2026-11-06 CVSS score added · Red Hat
References
More kyverno vulnerabilities
- TI-2024-32618 Kyverno's PolicyException objects can be created in any namespace by default CVSS 4.0HIGH 8.7
- TI-2026-57895 Kyverno before v1.13.0 Policy Bypass via Multiple Exceptions CVSS 4.0CRITICAL 9.4
- TI-2026-39369 Missing authorization in kyverno CVSS 3.1CRITICAL 9.6
- TI-2026-17733 Kyverno Cross-Namespace Privilege Escalation via Policy apiCall CVSS 3.1CRITICAL 10.0
- TI-2026-29924 Kyverno: ServiceAccount token leaked to external servers via apiCall service URL CVSS 3.1CRITICAL 9.1
- TI-2026-29524 kyverno apicall servicecall implicit bearer token injection leaks kyverno serviceaccount token CVSS 3.1HIGH 8.1
Sources
- CVE-2026-122318 · CVE Program
- CVE-2026-122318 · NVD
- FIRST EPSS
- GHSA-p8fx-8mgf-mvw3 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-122318 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences