CVE-2026-3833 (GCVE-0-2026-3833)
Vulnerability from cvelistv5
Published
2026-04-30 17:37
Modified
2026-06-02 15:34
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
Summary
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.
References
Impacted products
Vendor Product Version
Version: 0   
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   Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:3.8.10-4.el10_2   < *
    cpe:/o:redhat:enterprise_linux:10.2
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   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:3.6.16-8.el8_10.6   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/o:redhat:enterprise_linux:8::baseos
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   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:3.6.16-8.el8_10.6   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/o:redhat:enterprise_linux:8::baseos
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   Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:3.8.10-4.el9_8   < *
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
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   Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:3.8.10-4.el9_8   < *
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
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   Red Hat Red Hat Hardened Images Unaffected: 3.8.13-1.hum1   < *
    cpe:/a:redhat:hummingbird:1
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   Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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   Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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   Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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