CVE-2026-34001 (GCVE-0-2026-34001)

Vulnerability from cvelistv5 – Published: 2026-04-23 14:54 – Updated: 2026-04-23 16:22
VLAI?
Title
Xorg: xwayland: x.org x server: use-after-free vulnerability leads to server crash and potential memory corruption
Summary
A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence() function. An attacker with access to the X11 server can exploit this without user interaction, leading to a server crash and potentially enabling memory corruption. This could result in a denial of service or further compromise of the system.
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-825 - Expired Pointer Dereference
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 14:14
Credits
Red Hat would like to thank Jan-Niklas Sohn (TrendAI Zero Day Initiative) for reporting this issue.
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • 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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