Vulnerability · Published May 7, 2026 · Assigned by redhat

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

High 7.4

In plain English

A high-severity improper certificate validation in gnutls. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.4High
Exploit odds (30 days)0.5%top 58.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10gnutls3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:8gnutls3.6.16-8.el8_10.6ALSA-2026:20611
AlmaLinux:9gnutls3.8.10-4.el9_8ALSA-2026:20612
AlmaLinux:10gnutls-c++3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:8gnutls-c++3.6.16-8.el8_10.6ALSA-2026:20611
AlmaLinux:9gnutls-c++3.8.10-4.el9_8ALSA-2026:20612
AlmaLinux:10gnutls-dane3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:8gnutls-dane3.6.16-8.el8_10.6ALSA-2026:20611
AlmaLinux:9gnutls-dane3.8.10-4.el9_8ALSA-2026:20612
AlmaLinux:10gnutls-devel3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:8gnutls-devel3.6.16-8.el8_10.6ALSA-2026:20611
AlmaLinux:9gnutls-devel3.8.10-4.el9_8ALSA-2026:20612
AlmaLinux:10gnutls-fips3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:10gnutls-utils3.8.10-4.el10_2ALSA-2026:20613
AlmaLinux:8gnutls-utils3.6.16-8.el8_10.6ALSA-2026:20611
AlmaLinux:9gnutls-utils3.8.10-4.el9_8ALSA-2026:20612
Alpine:v3.20gnutls3.8.13-r0ALPINE-CVE-2026-42011
Alpine:v3.21gnutls3.8.13-r0ALPINE-CVE-2026-42011
Alpine:v3.22gnutls3.8.13-r0ALPINE-CVE-2026-42011
Alpine:v3.23gnutls3.8.13-r0ALPINE-CVE-2026-42011
Alpine:v3.24gnutls3.8.13-r0ALPINE-CVE-2026-42011
Debian:12gnutls283.7.9-2+deb12u7DEBIAN-CVE-2026-42011
Debian:13gnutls283.8.9-3+deb13u4DEBIAN-CVE-2026-42011
Debian:14gnutls283.8.13-1DEBIAN-CVE-2026-42011
Rocky Linux:10gnutls0:3.8.10-4.el10_2RLSA-2026:20613
Rocky Linux:8gnutls0:3.6.16-8.el8_10.6RLSA-2026:20611
Rocky Linux:9gnutls0:3.8.10-4.el9_8RLSA-2026:20612
Ubuntu:22.04:LTSgnutls283.7.3-4ubuntu1.9UBUNTU-CVE-2026-42011
Ubuntu:24.04:LTSgnutls283.8.3-1.1ubuntu3.6UBUNTU-CVE-2026-42011
Ubuntu:25.10gnutls283.8.9-3ubuntu2.2UBUNTU-CVE-2026-42011
Ubuntu:26.04:LTSgnutls283.8.12-2ubuntu1.1UBUNTU-CVE-2026-42011

Affected products (as reported)

VendorProductVersions
gnutls 0
Red Hat Red Hat Enterprise Linux 10 see references
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support see references
Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support see references
Red Hat Red Hat Enterprise Linux 8 see references
Red Hat Red Hat Enterprise Linux 8 see references
Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On see references
Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On see references
Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support see references
Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On see references
Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On see references
Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service see references
Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service see references
Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat Enterprise Linux 9 see references
Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions see references
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support see references
Red Hat Red Hat OpenShift Container Platform 4.12 see references
Red Hat Red Hat OpenShift Container Platform 4.16 see references
Red Hat Red Hat OpenShift Container Platform 4.17 see references
Red Hat Red Hat OpenShift Container Platform 4.18 see references
Red Hat Red Hat OpenShift Container Platform 4.19 see references
Red Hat Red Hat OpenShift Container Platform 4.20 see references
Red Hat Red Hat OpenShift Container Platform 4.21 see references

Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

References