CVE-2026-56000 (GCVE-0-2026-56000)
Vulnerability from cvelistv5 – Published: 2026-07-08 07:36 – Updated: 2026-07-08 12:42
VLAI
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 12:41 UTC
CWE
- CWE-416 - Use after free
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://gitlab.freedesktop.org/xorg/xserver/-/com… | patch |
| https://www.openwall.com/lists/oss-security/2026/… | vendor-advisory |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| X.Org | xorg-x11-server |
Affected:
0 , < 21.1.24
(rpm)
|
guessed | |
| X.Org | xwayland |
Affected:
0 , < 24.1.13
(rpmver)
|
guessed |
Date Public
2026-07-08 07:30
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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