CVE-2026-3833mediumCWE-178

CVE-2026-3833: medium-severity vulnerability in gnutls

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

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.6%
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
gnutlsRed Hat · Cert Manager support for Red Hat OpenShift release 1.17Red Hat · Cert Manager support for Red Hat OpenShift release 1.18Red Hat · Cert Manager support for Red Hat OpenShift release 1.20Red Hat · Red Hat Discovery 2Red Hat · Red Hat Enterprise Linux 10Red Hat · Red Hat Enterprise Linux 10.0 Extended Update SupportRed Hat · Red Hat Enterprise Linux 6Red Hat · Red Hat Enterprise Linux 7 Extended Lifecycle SupportRed Hat · Red Hat Enterprise Linux 8Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportRed Hat · Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnRed Hat · Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportRed Hat · Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnRed Hat · Red Hat Enterprise Linux 8.8 Telecommunications Update ServiceRed Hat · Red Hat Enterprise Linux 8.8 Update Services for SAP SolutionsRed Hat · Red Hat Enterprise Linux 9Red Hat · Red Hat Enterprise Linux 9.2 Update Services for SAP SolutionsRed Hat · Red Hat Enterprise Linux 9.4 Update Services for SAP SolutionsRed Hat · Red Hat Enterprise Linux 9.6 Extended Update SupportRed Hat · Red Hat Hardened ImagesRed Hat · Red Hat OpenShift AI 3.4Red Hat · Red Hat OpenShift Container Platform 4Red Hat · Red Hat OpenShift Container Platform 4.12Red Hat · Red Hat OpenShift Container Platform 4.13Red Hat · Red Hat OpenShift Container Platform 4.14Red Hat · Red Hat OpenShift Container Platform 4.15Red Hat · Red Hat OpenShift Container Platform 4.16Red Hat · Red Hat OpenShift Container Platform 4.17Red Hat · Red Hat OpenShift Container Platform 4.18Red Hat · Red Hat OpenShift Container Platform 4.19Red Hat · Red Hat Update Infrastructure 5
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