CVE-2026-42012

Gnutls: gnutls: certificate validation bypass due to improper handling of uri and srv sans

CVSS 3.1 7.1 HIGHCheck source for fixed versionsKEV status unknown

Original advisory

cve-program · CVE-2026-42012

Published

A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.

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Affected versions, risk and source history

Exploitation and risk

Source status

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Risk history

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Advisory history

4 saved versions

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3 Nov 2026 09:57:17 UTC