CVE-2025-61727

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

MEDIUM
6.5
CVSS Score
Published: December 3, 2025 at 07:37 PM UTC
Updated: October 18, 2026 at 05:10 PM UTC
2 products affected across 2 vendorsGoCrypto/x509

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.24.111.25 ≤ v < 1.25.5
0 ≤ v < 1.24.111.25.0 ≤ v < 1.25.51.25.0
Affected range stops below 1.24.11, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.25.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

Patch
Source: cverecord
https://go.dev/cl/723900
Issue Tracking
Source: cverecord
https://go.dev/issue/76442
Mailing ListRelease Notes
Source: cverecord
https://groups.google.com/g/golang-announce/c/8FJoBkPddm4
Vendor Advisory
Source: cverecord
https://pkg.go.dev/vuln/GO-2025-4175

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-295

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