---
id: "CVE-2026-93519"
kind: "vulnerability"
aliases: ["CVE-2026-93519"]
title: "X.Org X server: XFIXES pointer barrier overflow lets clients crash or run code"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "linux-desktop", "x.org", "xorg-server", "xwayland"]
not_affected_if: ["no-x-server", "patched-version"]
published_at: "2026-10-28T15:17:10+00:00"
first_seen_at: "2026-10-28T15:33:37+00:00"
updated_at: "2026-10-28T15:35:05+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93519", "first_seen_at": "2026-10-28T15:33:37+00:00"}]
---

# X.Org X server: XFIXES pointer barrier overflow lets clients crash or run code

A buffer overflow in the XFIXES extension's pointer barrier handling in X.Org X server (before 21.1.25) and XWayland (before 24.1.14) can be triggered by an authenticated X client. An attacker can crash the X server or potentially execute code in its context.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `Xorg -version` or `X -version` and compare against `21.1.25`.
- For XWayland, run `Xwayland -version` and compare against `24.1.14`.
- Check your distribution's package manager for the installed xorg-server or xwayland package version.

## Fix

- Upgrade X.Org X server to `21.1.25` or later.
- Upgrade XWayland to `24.1.14` or later.
- Apply your distribution's xorg-server and xwayland security updates.

## Timeline

- 2026-10-28T15:33:37+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-93519

## From the sources

A buffer overflow when handling pointer barriers in the XFIXES extension in X.Org X server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to crash or potentially execute code in X server context.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_