CVE-2025-61727

Improper application of excluded DNS name constraints when verifying wildcard names in crypto/x509

Published Dec 3, 2025 CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
Description
An excluded subdomain constraint in a certificate chain does not restrict the usage of wildcard SANs in the leaf certificate. For example a constraint that excludes the subdomain test.example.com does not prevent a leaf certificate from claiming the SAN *.example.com.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Golang
Golang go
CPEs cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
Vendors & Products Golang
Golang go
Type Values Removed Values Added
First Time appeared Go Standard Library
Go Standard Library crypto Tls
Vendors & Products Go Standard Library
Go Standard Library crypto Tls
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description An excluded subdomain constraint in a certificate chain does not restrict the usage of wildcard SANs in the leaf certificate. For example a constraint that excludes the subdomain test.example.com does not prevent a leaf certificate from claiming the SAN *.example.com.
Title Improper application of excluded DNS name constraints when verifying wildcard names in crypto/x509
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Go
Published
Updated
Dec 3, 2025, 10:06 PM
Reserved
Sep 30, 2025, 3:05 PM
Status
Analyzed
Published
Dec 3, 2025, 8:16 PM
Modified
Oct 18, 2026, 5:10 PM
Severity
Moderate
Public date
Dec 3, 2025, 7:37 PM