CVE-2026-27138

MEDIUM5.9EPSS 0.03%

Panic in name constraint checking for malformed certificates in crypto/x509

Published: 3/6/2026Modified: 5/15/2026

Description

Certificate verification can panic when a certificate in the chain has an empty DNS name and another certificate in the chain has excluded name constraints. This can crash programs that are either directly verifying X.509 certificate chains, or those that use TLS.

Affected packages (3)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1MEDIUM5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References (6)