---
id: "CVE-2026-109092"
page: "https://infrastack.ai/live/CVE-2026-109092"
kind: "vulnerability"
aliases: ["CVE-2026-109092"]
title: "X.Org XWayland and X Server: negative sizes let local clients run code"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["desktop", "infrastructure", "linux", "xorg", "xwayland"]
not_affected_if: ["no-x-server", "single-user-machine", "wayland-only-no-xwayland"]
published_at: "2026-11-13T15:17:29+00:00"
first_seen_at: "2026-11-13T15:46:15+00:00"
updated_at: "2026-11-13T15:48:22+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-109092", "first_seen_at": "2026-11-13T15:46:15+00:00"}]
exploit_sources: []
---

# X.Org XWayland and X Server: negative sizes let local clients run code

Link for people: https://infrastack.ai/live/CVE-2026-109092 (this .md is for agents)

XWayland and the X Server mishandle negative sizes in ProcXvShmPutImage requests. A local client that is already authenticated to the X server can crash it or execute code.

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

## How to check

- Check the installed XWayland version with `Xwayland -version`, and the X Server version with `Xorg -version`.
- Compare against the fixed versions: XWayland before `24.1.15` and X Server before `21.1.26` are affected.

## Fix

- XWayland: move to `24.1.15` or later.
- X Server: move to `21.1.26` or later.

## Timeline

- 2026-11-13T15:46:15+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-109092

## From the sources

Incorrectly handled negative sizes when processing ProcXvShmPutImage requests in the X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by local authenticated X clients to crash the X server or execute code.

---

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