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CVE-2026-27137 is a certificate validation flaw in Go's crypto/x509 package. When verifying a certificate chain that includes a certificate containing multiple email address name constraints sharing the same local part but different domain parts, the constraint processing logic does not correctly apply all relevant constraints. Instead, only the last matching email constraint is considered during validation. This results in incorrect enforcement of X.509 email address constraints during certificate chain verification and can cause malformed or non-compliant certificate chains to be accepted when they should be rejected.
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A certificate validation vulnerability in Go's crypto/x509 caused by incorrect enforcement of email constraints.
A vulnerability in Go crypto/x509 involving incorrect enforcement of email constraints.
A Go crypto/x509 vulnerability caused by incorrect enforcement of email constraints during certificate validation.
A vulnerability in Go crypto/x509 involving incorrect enforcement of email constraints.
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Cross-references every affected SKU, including bundled OEM variants.
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