Public vulnerability disclosure
CVE-2026-42012
Gnutls: gnutls: certificate validation bypass due to improper handling of uri and srv sans
publishedCWE-295
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.
Technical severity7.1 highCVSS 3.1 · CNA: redhat
Published2026-05-26Source updated 2026-11-03
Collected2026-11-032 attributed sources
Fixes and workarounds
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
gnutls
https://gitlab.com/gnutls/gnutls |
0 (affected) | CNA: redhat |
| Red Hat Enterprise Linux 10 Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.8.10-4.el10_2; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 10.0 Extended Update Support Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.8.9-9.el10_0.19; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:2.12.23-22.el6_10.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 7 Extended Lifecycle Support Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.3.29-9.el7_9.2; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8 Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.16-8.el8_10.6; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.14-10.el8_4.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-3.el8_4.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.14-10.el8_4.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-3.el8_4.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.16-5.el8_6.5; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-3.el8_6.2; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.16-5.el8_6.5; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-3.el8_6.2; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Telecommunications Update Service Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.16-7.el8_8.4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Telecommunications Update Service Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-4.el8_8.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.6.16-7.el8_8.4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions Red Hat libtasn1
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:4.13-4.el8_8.1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.8.10-4.el9_8; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.7.6-21.el9_2.7; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.8.3-4.el9_4.6; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9.6 Extended Update Support Red Hat gnutls
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:3.8.3-6.el9_6.4; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.20 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 4.20.9.6.202610242033-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.21 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 4.21.9.6.202610241345-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4.22 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
≥ 4.22.9.8.202610241758-0; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.17 Red Hat cert-manager/jetstack-cert-manager-acmesolver-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791371080; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.17 Red Hat cert-manager/jetstack-cert-manager-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791371069; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.17 Red Hat cert-manager/cert-manager-operator-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791788287; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.17 Red Hat cert-manager/cert-manager-operator-bundle
https://catalog.redhat.com/software/containers/ |
≥ 1791970484; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.18 Red Hat cert-manager/jetstack-cert-manager-acmesolver-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791459707; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.18 Red Hat cert-manager/jetstack-cert-manager-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791459711; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.18 Red Hat cert-manager/cert-manager-istio-csr-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1791459759; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.18 Red Hat cert-manager/cert-manager-operator-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1789029076; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.18 Red Hat cert-manager/cert-manager-operator-bundle
https://catalog.redhat.com/software/containers/ |
≥ 1791966259; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Cert Manager support for Red Hat OpenShift release 1.20 Red Hat cert-manager/cert-manager-trust-manager-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1790598593; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Discovery 2 Red Hat discovery/discovery-server-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1782159791; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Discovery 2 Red Hat discovery/discovery-ui-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1782166952; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Hardened Images Red Hat gnutls-main
https://catalog.redhat.com/software/containers/ |
≥ 3.8.13-1.hum1; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift AI 3.4 Red Hat rhai/base-image-neuron-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1790703542; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/cds-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1781525684; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/haproxy-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1781525671; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/installer-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1781525693; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/rhua-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1781525739; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/cds-kubernetes-tp-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1787241211; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/installer-tp-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1787135742; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Update Infrastructure 5 Red Hat rhui5/rhua-tp-rhel9
https://catalog.redhat.com/software/containers/ |
≥ 1787241260; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4 Red Hat openshift4/ose-hypershift-rhel9
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unaffected |
CNA: redhat |
| Red Hat OpenShift Container Platform 4 Red Hat openshift/ose-rhel-coreos-8
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
| Red Hat OpenShift Container Platform 5 Red Hat openshift/ose-rhel-coreos-9
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: affected |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.1 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N | CNA: redhat |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://access.redhat.com/errata/RHSA-2026:13274CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20611CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20612CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:20613CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:26319CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:26409CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:29197CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:30004CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:30849CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:30850CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:32962CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:33125CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:41921CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:43575CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:58981CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:72502CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:74674CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82304CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82322CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82347CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82354CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82372CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82857CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:82888CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:89197CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:89232CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:89333CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:94442CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-42012CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2467441CNA: redhat · issue-tracking, x_refsource_REDHAT
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-7CNA: redhat
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