---
id: "CVE-2026-93521"
kind: "vulnerability"
aliases: ["CVE-2026-93521"]
title: "X.Org X Server: RandR request overflow lets a client crash or run code"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "linux-desktop", "workstation", "x.org", "xwayland"]
not_affected_if: ["headless-server", "no-x-server"]
published_at: "2026-10-28T16:17:10+00:00"
first_seen_at: "2026-10-28T16:33:49+00:00"
updated_at: "2026-10-28T16:35:50+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93521", "first_seen_at": "2026-10-28T16:33:49+00:00"}]
---

# X.Org X Server: RandR request overflow lets a client crash or run code

A buffer overflow in the RandR ChangeProviderProperty request in X.Org X Server before 2.1.25 and XWayland before 24.4.14 lets an authenticated X client crash the server or execute code in its context. The attacker needs only a connection to the X server as a client.

_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 `2.1.25` for X.Org Server and `24.4.14` for XWayland
- Run `Xwayland -version` on Wayland sessions that use XWayland
- unknown for other checks, since the sources do not name a configuration

## Fix

- Upgrade X.Org X Server to `2.1.25` or later
- Upgrade XWayland to `24.4.14` or later
- Install the fixed packages from your distribution once it ships them

## Timeline

- 2026-10-28T16:33:49+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-93521

## From the sources

A buffer overflow in RandR
ChangeProviderProperty requests in X.Org X Server before 2.1.25 and XWayland before 24.4.14 could be used by authenticated X clients to crash or execute code within the X server context.

---

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