CVE-2026-33999 (GCVE-0-2026-33999)

Vulnerability from cvelistv5 – Published: 2026-04-23 14:53 – Updated: 2026-04-23 14:53
VLAI?
Title
Xorg: xwayland: x.org x server: denial of service via integer underflow in xkb compatibility map handling
Summary
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.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
References
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
 Create a notification for this product.
Date Public ?
2026-04-23 14:11
Credits
Red Hat would like to thank Jan-Niklas Sohn (TrendAI Zero Day Initiative) for reporting this issue.
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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