Bug 2567773 (CVE-2026-122318)

Summary: CVE-2026-122318 github.com/kyverno/kyverno: Kyverno: Image verification bypass via missing Subject Alternative Name in signing certificates
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: gbenhaim, niyer, twaugh
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Kyverno. This vulnerability allows an attacker possessing a certificate issued by a trusted private authority to bypass image verification policies. By omitting the Subject Alternative Name (SAN) from a signing certificate, identity checks on image signers are skipped during policy evaluation. Consequently, an attacker can deploy unauthorized or malicious container images into the cluster despite configured signer restrictions.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-11-05 22:24:55 UTC 
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.