CVE-2026-42012

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

HIGH
7.1
CVSS Score
Published: May 26, 2026 at 09:29 PM UTC
Updated: October 29, 2026 at 06:17 AM UTC
2 products affected across 1 vendorEnterprise LinuxOpenShift Container Platform

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Severity
HIGH7.1
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions6
Vendor states this is fixed in 0:3.3.29-9.el7_9.2 (unaffected)
Vendor states this is fixed in 0:3.6.14-10.el8_4.1 (unaffected)
Vendor states this is fixed in 0:3.6.16-5.el8_6.5 (unaffected)
Vendor states this is fixed in 0:3.6.16-7.el8_8.4 (unaffected)
Vendor states this is fixed in 0:3.6.16-8.el8_10.6 (unaffected)
Vendor states this is fixed in 0:3.7.6-21.el9_2.7 (unaffected)
Vendor states this is fixed in 0:3.8.10-4.el10_2 (unaffected)
Vendor states this is fixed in 0:3.8.10-4.el9_8 (unaffected)
Vendor states this is fixed in 0:3.8.3-4.el9_4.6 (unaffected)
Vendor states this is fixed in 0:3.8.3-6.el9_6.4 (unaffected)
Vendor states this is fixed in 0:3.8.9-9.el10_0.19 (unaffected)
Vendor states this is fixed in 0:4.13-3.el8_4.1 (unaffected)
Vendor states this is fixed in 0:4.13-3.el8_6.2 (unaffected)
Vendor states this is fixed in 0:4.13-4.el8_8.1 (unaffected)
All versions4
Vendor states this is fixed in 4 (unknown)

References (30)

VDB Entryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/security/cve/CVE-2026-42012
Issue Trackingx_refsource_REDHAT
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2467441
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:20611
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:20613
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:20612
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:26319
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:26409
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:29197

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.1HIGHredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-295

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