CVE-2026-93517

HIGH

8.5

CVSS v4

Description

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

CWE-122Heap-based Buffer Overflow

How to fix

Remediation Available

xorg-serverDebian

Fixed in:2:21.1.25-1CVE-2026-93517

xwaylandDebian

Fixed in:2:24.1.14-1CVE-2026-93517

xorg-x11-serverRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-serverRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XdmxRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XdmxRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xdmx-debuginfoRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xdmx-debuginfoRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XephyrRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XephyrRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xephyr-debuginfoRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xephyr-debuginfoRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XnestRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XnestRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xnest-debuginfoRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xnest-debuginfoRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XorgRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XorgRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xorg-debuginfoRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xorg-debuginfoRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XvfbRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XvfbRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xvfb-debuginfoRocky

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-Xvfb-debuginfoRed Hat / RHEL

Fixed in:0:1.20.11-28.el8_10.5RHSA-2026:89747

Fixed in:0:1.20.11-34.el9_8.5RHSA-2026:84574

xorg-x11-server-XwaylandRocky

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

xorg-x11-server-XwaylandRed Hat / RHEL

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

xorg-x11-server-Xwayland-debuginfoRocky

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

xorg-x11-server-Xwayland-debuginfoRed Hat / RHEL

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

xorg-x11-server-Xwayland-debugsourceRed Hat / RHEL

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

xorg-x11-server-Xwayland-debugsourceRocky

Fixed in:0:24.1.9-4.el10_2.4RHSA-2026:85191

Fixed in:0:21.1.3-20.el8_10.4RHSA-2026:86907

This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v4 Vector

Exploitability

Attack VectorLocal

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

Impact

CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploit Intelligence

0.19%probability of exploitation in 30 days

9thpercentile

Low risk: more likely to be exploited than 9% of all known CVEs.

References

Other references1

gitlab.freedesktop.org

Related Vulnerabilities

Other CWE-122 (Heap-based Buffer Overflow) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2015-3113	Critical	9.8	100%	KEV	Fix
CVE-2020-25687	Medium	5.9	89%	-	Fix
CVE-2020-25683	Medium	5.9	89%	-	Fix
CVE-2024-26256	High	7.8	88%	-	Fix
CVE-2009-3459	High	8.8	87%	KEV	Fix
CVE-2021-21017	High	8.8	86%	KEV	-

Common questions

How do I fix CVE-2026-93517?

Published advisories record a fix for 42 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2026-93517 being actively exploited?

Not that we know of. CVE-2026-93517 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.19% is the estimated probability that it will be exploited in the next 30 days. That is higher than 9% of all scored CVEs.

How severe is CVE-2026-93517?

CVE-2026-93517 has a CVSS v4 base score of 8.5, rated important. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-93517 affect?

Published advisories record a fix for xorg-server (Debian), xwayland (Debian), xorg-x11-server (Red Hat / RHEL), xorg-x11-server (Rocky), and 38 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-93517

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-10-28.