CVE-2026-27137highCWE-295

CVE-2026-27137: high-severity vulnerability in Go standard library crypto/x509

Incorrect enforcement of email constraints in crypto/x509

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.7%
When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly applied, and only the last constraint will be considered.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Go standard library · crypto/x509
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