CVE-2026-27138

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

Medium · published March 6, 2026

CVSS v3.1
5.9
EPSS
0%
Percentile
25.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00333 · 25.3th percentile
Published
2026-03-06T21:28Z
EPSS history
Timeline
  • 06 MAR 21:28Z
    Panic in name constraint checking for malformed certificates in crypto/x509
    cvelistv5