CVE-2026-42011
Gnutls: gnutls: security bypass due to incorrect name constraint handling
CVSS Score
7.4
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-295 |
| Published | May 7, 2026 |
| Last Updated | Sep 3, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
Red Hat / Red Hat Enterprise Linux 10
All versions affected Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support
All versions affected Red Hat / Red Hat Enterprise Linux 8
All versions affected Red Hat / Red Hat Enterprise Linux 8
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions
All versions affected Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.12
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.16
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.17
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.18
All versions affected Red Hat / Red Hat OpenShift Container Platform 4.19
All versions affected Red Hat / Red Hat Discovery 2
All versions affected Red Hat / Red Hat Discovery 2
All versions affected Red Hat / Red Hat Hardened Images
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Update Infrastructure 5
All versions affected Red Hat / Red Hat Enterprise Linux 6
All versions affected Red Hat / Red Hat OpenShift Container Platform 4
All versions affected Red Hat / Red Hat OpenShift Container Platform 4
All versions affected References
access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13274 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:20611 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:20612 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:20613 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26319 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26409 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:29197 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30004 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30849 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:30850 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:32962 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:33125 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:40762 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:41921 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:43575 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:56853 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:57483 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:58981 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:59831 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:60019 access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-42011 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2467437 gnutls.org: https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-6
Credits
Red Hat would like to thank Haruto Kimura (Stella) for reporting this issue.