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 (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
X.Org xorg-x11-server Affected: 0 , < 21.1.24 (rpm)
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X.Org xwayland Affected: 0 , < 24.1.13 (rpmver)
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
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.