CVE-2025-61727Improper Certificate Validation in Standard Library Crypto X509

Severity
6.5MEDIUMNVD
EPSS
0.0%
top 98.63%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedDec 3
Latest updateApr 16

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.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NExploitability: 3.9 | Impact: 2.5

Affected Packages2 packages

NVDgolang/go1.251.25.5+1
CVEListV5go_standard_library/crypto_x5091.25.01.25.5+1

Patches

🔴Vulnerability Details

5
GHSA
webpki: Name constraints were accepted for certificates asserting a wildcard name2026-04-16
CVEList
Improper application of excluded DNS name constraints when verifying wildcard names in crypto/x5092025-12-03
OSV
CVE-2025-61727: An excluded subdomain constraint in a certificate chain does not restrict the usage of wildcard SANs in the leaf certificate2025-12-03
GHSA
GHSA-5mh9-3jwc-rp59: An excluded subdomain constraint in a certificate chain does not restrict the usage of wildcard SANs in the leaf certificate2025-12-03
OSV
Improper application of excluded DNS name constraints when verifying wildcard names in crypto/x5092025-12-02

📋Vendor Advisories

3
Microsoft
Improper application of excluded DNS name constraints when verifying wildcard names in crypto/x5092025-12-09
Red Hat
golang: crypto/x509: excluded subdomain constraint does not restrict wildcard SANs2025-12-03
Debian
CVE-2025-61727: golang-1.15 - An excluded subdomain constraint in a certificate chain does not restrict the us...2025

💬Community

1
Bugzilla
CVE-2025-61727 golang: crypto/x509: excluded subdomain constraint does not restrict wildcard SANs2025-12-03
CVE-2025-61727 — Improper Certificate Validation | cvebase