CVE-2026-3833
Gnutls: gnutls: policy bypass due to case-sensitive nameconstraints comparison
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-178 |
| Published | Apr 30, 2026 |
| Last Updated | Jun 2, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
Red Hat / Red Hat Enterprise Linux 10
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 9
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Hardened Images
All versions affected Red Hat / Red Hat Enterprise Linux 6
All versions affected Red Hat / Red Hat Enterprise Linux 7
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/security/cve/CVE-2026-3833 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2445763 gitlab.com: https://gitlab.com/gnutls/gnutls/-/issues/1803