Description
A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of `nameConstraints` labels, specifically for `dNSName` (DNS) or `rfc822Name` (email) constraints within `excludedSubtrees` or `permittedSubtrees`. A remote attacker can exploit this by crafting a leaf certificate with casing differences in the Subject Alternative Name (SAN), leading to a policy bypass where a certificate that should be rejected is instead accepted. This could result in unauthorized access or information disclosure.
CVSS breakdown
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
Affected products
- gnu / gnutls
- RedHat / enterprise_linux10.0 – 10.0
- RedHat / enterprise_linux8.0 – 8.0
- RedHat / enterprise_linux9.0 – 9.0
- RedHat / enterprise_linux6.0 – 6.0
- RedHat / enterprise_linux7.0 – 7.0
- RedHat / hardened_images
- RedHat / openshift_container_platform4.0 – 4.0
References
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:13274
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:20611
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:20612
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:20613
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:26319
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:26409
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:29197
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:30004
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:30849
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:30850
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:32962
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:33125
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:41921
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:43575
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:57402
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2026:58981
- VENDOR_ADVISORYhttps://access.redhat.com/security/cve/CVE-2026-3833
- MISChttps://bugzilla.redhat.com/show_bug.cgi?id=2445763
- MISChttps://gitlab.com/gnutls/gnutls/-/issues/1803
Updated 8m ago · 8 sources