Bug 2445763 (CVE-2026-3833) - CVE-2026-3833 gnutls: GnuTLS: Policy bypass due to case-sensitive nameConstraints comparison
Summary: CVE-2026-3833 gnutls: GnuTLS: Policy bypass due to case-sensitive nameConstra...
Keywords:
Status: NEW
Alias: CVE-2026-3833
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2477365
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-03-09 14:03 UTC by OSIDB Bzimport
Modified: 2026-06-02 08:28 UTC (History)
7 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2026:20910 0 None None None 2026-05-26 12:27:02 UTC
Red Hat Product Errata RHBA-2026:20937 0 None None None 2026-05-26 15:25:14 UTC
Red Hat Product Errata RHSA-2026:20611 0 None None None 2026-05-26 06:15:25 UTC
Red Hat Product Errata RHSA-2026:20612 0 None None None 2026-05-26 06:20:03 UTC
Red Hat Product Errata RHSA-2026:20613 0 None None None 2026-05-26 06:17:57 UTC

Description OSIDB Bzimport 2026-03-09 14:03:06 UTC 
gnutls compares nameConstraints labels using a case-sensitive memcmp path without an ascii-casefold canonicalization step. when excludedSubtrees/permittedSubtrees dNSName (dns) or rfc822Name (email) constraints are present, attacker-controlled casing differences in the leaf certificate SAN can cause a false accept (policy bypass) where the certificate should be rejected.
Comment 3 errata-xmlrpc 2026-05-26 06:15:24 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:20611 https://access.redhat.com/errata/RHSA-2026:20611
Comment 4 errata-xmlrpc 2026-05-26 06:17:56 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:20613 https://access.redhat.com/errata/RHSA-2026:20613
Comment 5 errata-xmlrpc 2026-05-26 06:20:01 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:20612 https://access.redhat.com/errata/RHSA-2026:20612
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