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CVE-2026-42012: Improper Certificate Validation

0
High
VulnerabilityCVE-2026-42012cvecve-2026-42012
Published: 05/26/2026 (05/26/2026, 21:29:26 UTC)
Source: CVE Database V5

Description

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.

CVSS v3.1

Score 7.1high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
Low
Integrity
High
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N

Technical Details

Data Version
5.2
Assigner Short Name
redhat
Date Reserved
2026-04-23T11:23:46.517Z
Cvss Version
3.1
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://access.redhat.com/security/cve/CVE-2026-42012","vendor":"Red Hat"}]

Threat ID: 6a161534e29bf47b506c521c

Added to database: 05/26/2026, 21:48:36 UTC

Last enriched: 07/21/2026, 18:22:57 UTC

Last updated: 09/10/2026, 19:36:53 UTC

Views: 220

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