---
id: CVE-2026-93515
title: .Org Server Present Extension Use-After-Free
summary: "A use-after-free in\_present_clear_window_notifies()  in the X.org X Server before 21.1.25 and X Wayland before 24.1.14 could be used by malicious X clients to crash or potentially execute code in the X server context."
severity: medium
cvss: 6.8
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-416
vendor: X.org
product: xorg-x11-server
affected:
  - xorg-x11-server < 21.1.25
  - xwayland < 24.1.14
published: '2026-10-28'
updated: '2026-10-28'
sourceUpdated: '2026-10-28T12:39:44.890Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-93515'
references:
  - url: >-
      https://gitlab.freedesktop.org/xorg/xserver/-/commit/1b6955c3108e6b43433aefe860070708e6f43d1b
tags:
  - cve.org
ingestedAt: '2026-10-28T13:11:23.675Z'
---

## Overview

A use-after-free in present_clear_window_notifies()  in the X.org X Server before 21.1.25 and X Wayland before 24.1.14 could be used by malicious X clients to crash or potentially execute code in the X server context.

## Affected

- `xorg-x11-server < 21.1.25`
- `xwayland < 24.1.14`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.