CVE-2026-3833

MEDIUM 6.5

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

CVSS Score

6.5

EPSS Score

0.6%

EPSS Percentile

43th

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	Jul 22, 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 10.0 Extended Update Support

All versions affected

Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support

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 8.4 Advanced Mission Critical Update Support

All versions affected

Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

All versions affected

Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

All versions affected

Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

All versions affected

Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

All versions affected

Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

All versions affected

Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

All versions affected

Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

All versions affected

Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service

All versions affected

Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service

All versions affected

Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

All versions affected

Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

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 Enterprise Linux 9.2 Update Services for SAP Solutions

All versions affected

Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

All versions affected

Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support

All versions affected

Red Hat / Red Hat Discovery 2

All versions affected

Red Hat / Red Hat Discovery 2

All versions affected

Red Hat / Red Hat Hardened Images

All versions affected

Red Hat / Red Hat Update Infrastructure 5

All versions affected

Red Hat / Red Hat Update Infrastructure 5

All versions affected

Red Hat / Red Hat Update Infrastructure 5

All versions affected

Red Hat / Red Hat Update Infrastructure 5

All versions affected

Red Hat / Red Hat Enterprise Linux 6

All versions affected

Red Hat / Red Hat OpenShift Container Platform 4

All versions affected

Red Hat / Red Hat OpenShift Container Platform 4

All versions affected

References

NVD ↗ CVE.org ↗ EPSS Data ↗