CVE-2026-56000 (GCVE-0-2026-56000)

Vulnerability from cvelistv5 – Published: 2026-07-08 07:36 – Updated: 2026-07-08 12:42
VLAI
Title
xorg-x11-server / xwayland GLX contextTags Use-After-Free in CommonMakeCurrent()
Summary
Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.
Severity
9 (Critical)
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 12:41 UTC
CWE
Assigner
suse CNA under the mitre root
CNA scorecard B 80/100 over 118 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
X.Org xorg-x11-server Affected: 0 , < 21.1.24 (rpm)
guessed Create a notification for this product.
X.Org xwayland Affected: 0 , < 24.1.13 (rpmver)
guessed Create a notification for this product.
Date Public
2026-07-08 07:30
Credits
Anonymous working with Trend Micro Zero Day Initiative.
Show details on NVD website
To clipboard 

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