CVE-2026-3833
Gnutls: gnutls: policy bypass due to case-sensitive nameconstraints comparison
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:LConfidentialityLow
I:LIntegrityLow
A:NAvailabilityNone
Weaknesses
Affected Products
Red Hat Inc.
commercial·USaka Red Hat, redhat
gnu
oss-project·USaka g. nu
Novell Inc.
commercial·US
Сообщество свободного программного обеспечения
oss-projectaka fsf
АО «ИВК»
commercial·RUaka ivk
Free Software Foundation, Inc.
oss-project·USaka free software foundation, fsf
and 25 more affected products View all →
Exploitability
Official Patch Available
Workaround Available
References
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
and 27 more references View all →
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