# CVE-2026-42011: Gnutls: gnutls: security bypass due to incorrect name constraint handling

Status: published. Published: 2026-05-07. Updated: 2026-11-11.

A flaw was found in gnutls. This vulnerability occurs because permitted name constraints were incorrectly ignored when previous Certificate Authorities (CAs) only had excluded name constraints. A remote attacker could exploit this to bypass critical name constraint checks during certificate validation. This bypass could lead to the acceptance of invalid certificates, potentially enabling spoofing or man-in-the-middle attacks against affected systems.

## Remediation

No remediation reported in collected sources

## Affected products and versions

-  /  (gnutls): 0 (affected). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (gnutls): ≥ 0:3.8.10-4.el10_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (gnutls): ≥ 0:3.8.9-9.el10_0.19; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (gnutls): ≥ 0:3.3.29-9.el7_9.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (gnutls): ≥ 0:3.6.16-8.el8_10.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (gnutls): ≥ 0:3.6.14-10.el8_4.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (libtasn1): ≥ 0:4.13-3.el8_4.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (gnutls): ≥ 0:3.6.14-10.el8_4.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (libtasn1): ≥ 0:4.13-3.el8_4.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (gnutls): ≥ 0:3.6.16-5.el8_6.5; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (libtasn1): ≥ 0:4.13-3.el8_6.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (gnutls): ≥ 0:3.6.16-5.el8_6.5; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (libtasn1): ≥ 0:4.13-3.el8_6.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (gnutls): ≥ 0:3.6.16-7.el8_8.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (libtasn1): ≥ 0:4.13-4.el8_8.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (gnutls): ≥ 0:3.6.16-7.el8_8.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (libtasn1): ≥ 0:4.13-4.el8_8.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (gnutls): ≥ 0:3.8.10-4.el9_8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (gnutls): ≥ 0:3.7.6-21.el9_2.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (gnutls): ≥ 0:3.8.3-4.el9_4.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (gnutls): ≥ 0:3.8.3-6.el9_6.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.12 (openshift/ose-rhel-coreos-8): ≥ 412.86.202608241157-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.13 (openshift/ose-rhel-coreos-9): ≥ 413.92.202611041925-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.14 (openshift/ose-rhel-coreos-9): ≥ 414.92.202611040941-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.16 (openshift/ose-rhel-coreos-9): ≥ 416.94.202608150307-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.17 (openshift/ose-rhel-coreos-9): ≥ 417.94.202608250221-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.18 (openshift/ose-rhel-coreos-9): ≥ 418.94.202608142238-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.19 (openshift/ose-rhel-coreos-9): ≥ 4.19.9.6.202607151909-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.20 (openshift/ose-rhel-coreos-9): ≥ 4.20.9.6.202610242033-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.21 (openshift/ose-rhel-coreos-9): ≥ 4.21.9.6.202610241345-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4.22 (openshift/ose-rhel-coreos-9): ≥ 4.22.9.8.202610241758-0; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.17 (cert-manager/jetstack-cert-manager-acmesolver-rhel9): ≥ 1791371080; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.17 (cert-manager/jetstack-cert-manager-rhel9): ≥ 1791371069; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.17 (cert-manager/cert-manager-operator-rhel9): ≥ 1791788287; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.17 (cert-manager/cert-manager-operator-bundle): ≥ 1791970484; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.18 (cert-manager/jetstack-cert-manager-acmesolver-rhel9): ≥ 1791459707; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.18 (cert-manager/jetstack-cert-manager-rhel9): ≥ 1791459711; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.18 (cert-manager/cert-manager-istio-csr-rhel9): ≥ 1791459759; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.18 (cert-manager/cert-manager-operator-rhel9): ≥ 1789029076; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.18 (cert-manager/cert-manager-operator-bundle): ≥ 1791966259; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Cert Manager support for Red Hat OpenShift release 1.20 (cert-manager/cert-manager-trust-manager-rhel9): ≥ 1790598593; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Discovery 2 (discovery/discovery-server-rhel9): ≥ 1782159791; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Discovery 2 (discovery/discovery-ui-rhel9): ≥ 1782166952; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Hardened Images (gnutls-main): ≥ 3.8.13-1.hum1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat OpenShift AI 3.4 (rhai/base-image-neuron-rhel9): ≥ 1790703542; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/cds-rhel9): ≥ 1781525684; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/haproxy-rhel9): ≥ 1781525671; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/installer-rhel9): ≥ 1781525693; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/rhua-rhel9): ≥ 1781525739; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/cds-kubernetes-tp-rhel9): ≥ 1787241211; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/installer-tp-rhel9): ≥ 1787135742; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Update Infrastructure 5 (rhui5/rhua-tp-rhel9): ≥ 1787241260; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (gnutls): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 4 (openshift4/ose-hypershift-rhel9): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat OpenShift Container Platform 5 (openshift/ose-rhel-coreos-9): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 7.4 (high); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N; source: CNA: redhat

- CVSS 3.1: 7.4 (high); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N; source: NVD: secalert@redhat.com

- CISA KEV: No listing in collected sources

- EPSS: 0.47% as of 2026-11-10; percentile 41.38%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-295

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2026:13274 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:20611 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:20612 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:20613 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26319 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26409 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:29197 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:30004 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:30849 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:30850 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:32962 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:33125 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:40762 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:41921 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:43575 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:56853 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:57483 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:58981 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:59831 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:60019 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:72502 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:74674 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82304 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82322 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82347 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82354 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82372 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82857 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:82888 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:89197 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:89232 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:89333 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:95508 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:95745 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-42011 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2467437 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-6 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2026:13274 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:20611 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:20612 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:20613 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26319 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26409 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:29197 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:30004 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:30849 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:30850 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:32962 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:33125 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:40762 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:41921 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:43575 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:56853 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:57483 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:58981 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:59831 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:60019 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:72502 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:74674 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82304 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82322 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82347 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82354 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82372 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82857 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:82888 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:89197 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:89232 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:89333 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:95508 (secalert@redhat.com)

- https://access.redhat.com/security/cve/CVE-2026-42011 (secalert@redhat.com)

- https://bugzilla.redhat.com/show_bug.cgi?id=2467437 (secalert@redhat.com)

- https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-6 (secalert@redhat.com)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-42011; retrieved 2026-11-11; source updated 2026-11-11

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42011; retrieved 2026-11-10; source updated 2026-11-09

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-42011; retrieved 2026-11-11; source updated Not reported

Revision: 5dc5ba3b25bbafe222ee0b657c2a29234b918af48c75015902b5f55e1dc8b5f5

Canonical: https://y2.dev/cve/CVE-2026-42011

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