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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-33999 Detail

Description

A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of service (DoS) or other severe impacts.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://access.redhat.com/errata/RHSA-2026:10739 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:11352 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:11369 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:11388 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:11656 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:11692 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:13414 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:19125 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:19342 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:19343 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:19344 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20547 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20555 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20557 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20558 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20560 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20561 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20562 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20563 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20575 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20576 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:20590 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21699 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21712 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21715 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21716 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21718 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21741 Red Hat, Inc.
https://access.redhat.com/errata/RHSA-2026:21742 Red Hat, Inc.
https://access.redhat.com/security/cve/CVE-2026-33999 Red Hat, Inc.
https://bugzilla.redhat.com/show_bug.cgi?id=2451106 Red Hat, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-191 Integer Underflow (Wrap or Wraparound) Red Hat, Inc.  

Change History

18 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-33999
NVD Published Date:
04/23/2026
NVD Last Modified:
05/28/2026
Source:
Red Hat, Inc.