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: 2026-07-22 14:35 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
Red Hat Product Errata RHSA-2026:26409 0 None None None 2026-06-16 16:39:20 UTC
Red Hat Product Errata RHSA-2026:30004 0 None None None 2026-06-25 18:07:31 UTC
Red Hat Product Errata RHSA-2026:30849 0 None None None 2026-06-29 02:48:26 UTC
Red Hat Product Errata RHSA-2026:30850 0 None None None 2026-06-29 02:30:09 UTC
Red Hat Product Errata RHSA-2026:32962 0 None None None 2026-06-29 09:47:30 UTC
Red Hat Product Errata RHSA-2026:33125 0 None None None 2026-06-29 15:07:21 UTC
Red Hat Product Errata RHSA-2026:41921 0 None None None 2026-07-20 06:27:56 UTC
Red Hat Product Errata RHSA-2026:43575 0 None None None 2026-07-22 14:35:13 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
Comment 11 errata-xmlrpc 2026-06-16 16:39:18 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:26409 https://access.redhat.com/errata/RHSA-2026:26409
Comment 12 errata-xmlrpc 2026-06-25 18:07:30 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:30004 https://access.redhat.com/errata/RHSA-2026:30004
Comment 13 errata-xmlrpc 2026-06-29 02:30:08 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:30850 https://access.redhat.com/errata/RHSA-2026:30850
Comment 14 errata-xmlrpc 2026-06-29 02:48:24 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Via RHSA-2026:30849 https://access.redhat.com/errata/RHSA-2026:30849
Comment 15 errata-xmlrpc 2026-06-29 09:47:28 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:32962 https://access.redhat.com/errata/RHSA-2026:32962
Comment 16 errata-xmlrpc 2026-06-29 15:07:20 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Via RHSA-2026:33125 https://access.redhat.com/errata/RHSA-2026:33125
Comment 17 errata-xmlrpc 2026-07-20 06:27:55 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:41921 https://access.redhat.com/errata/RHSA-2026:41921
Comment 18 errata-xmlrpc 2026-07-22 14:35:12 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:43575 https://access.redhat.com/errata/RHSA-2026:43575
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