High severity · published May 7, 2026
CVE-2026-42011
Gnutls: gnutls: security bypass due to incorrect name constraint handling
7.4
CVSS
0.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CM
Cert Manager support for Red Hat OpenShift release 1.17 · Red Hat
All versions, or not specified · source: vendor
CM
Cert Manager support for Red Hat OpenShift release 1.18 · Red Hat
All versions, or not specified · source: vendor
CM
Cert Manager support for Red Hat OpenShift release 1.20 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Discovery 2 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 7 Extended Lifecycle Support · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On · Red Hat
All versions, or not specified · source: vendor
Affected product
CM
Cert Manager support for Red Hat OpenShift release 1.17
Red Hat
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42011
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-42011
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:13274
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:20611
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:20612
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:20613
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:26319
vendor-advisory
https://access.redhat.com/errata/RHSA-2026:26409
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