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CVE-2026-3833

Gnutls: gnutls: policy bypass due to case-sensitive nameconstraints comparison

Published: Apr 30, 2026Updated: Jun 17, 2026 Sources: CVE List NVD BDUCWE-178
6.5MEDIUM
NVD MITRE
EPSS Score
0.5%
Top 60.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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

AV:NAC:LPR:NUI:NS:UC:LI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-178

Affected Products

Red Hat Enterprise LinuxRed Hat Inc.
On-premOS
Operating Systems / linux-distro
openSUSE TumbleweedNovell Inc.
On-prem
Operating Systems / linux-distro
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Red Hat OpenShift Container PlatformRed Hat Inc.
On-prem
Operating Systems / linux-distro
АЛЬТ СП 10АО «ИВК»
On-premOS
Operating Systems / linux-distro
red hat inc.commercialUSOperating Systemsaka red hat
novell inc.commercialUSOperating Systems
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ао «ивк»commercialRUOperating Systemsaka ivk
and 16 more affected products View all →

Exploitability

Official Patch Available
Workaround Available

References

https://gitlab.com/gnutls/gnutls/-/issues/1803
gitlab.com
https://access.redhat.com/security/cve/cve-2026-3833
access.redhat.com
https://security-tracker.debian.org/tracker/CVE-2026-3833
security-tracker.debian.org
and 11 more references View all →

Timeline

Published
Apr 30, 2026
Last Updated
Jun 17, 2026

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