Case-Sensitive Comparison Flaw in GnuTLS Affects Remote Security
CVE-2026-3833

6.5MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Vendor
CVE Published:
30 April 2026

What is CVE-2026-3833?

A vulnerability in GnuTLS arises from its case-sensitive comparison of nameConstraints labels for DNS and email constraints. This design flaw enables an attacker to exploit the system by creating a specially crafted leaf certificate that utilizes varying casing in the Subject Alternative Name (SAN). Consequently, this can lead to a policy bypass wherein a certificate that should ideally be rejected is accepted, posing risks of unauthorized access and potential information disclosure.

References

https://access.redhat.com/security/cve/CVE-2026-3833
vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2445763
issue-trackingx_refsource_REDHAT
https://gitlab.com/gnutls/gnutls/-/issues/1803

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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