CVE-2026-27138

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/752183	Mailing List
https://go.dev/issue/77953	Issue Tracking
https://groups.google.com/g/golang-announce/c/EdhZqrQ98hk	Release Notes
https://pkg.go.dev/vuln/GO-2026-4600	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:golang:go:1.26.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-06 22:16

Updated : 2026-06-17 10:26

NVD link : CVE-2026-27138

Mitre link : CVE-2026-27138

CVE.ORG link : CVE-2026-27138

JSON object : View

Products Affected

golang

go

CWE

CWE-295

Improper Certificate Validation

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