CVE-2026-109904

X.Org Server XRes QueryClientIds Request Size Overflow

publishedCWE-126

A buffer overread caused by an integer-overflow in Proc/SProcXResQueryClientIds in X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by attackers on authenticated X clients to crash the server or leak out information.

Technical severity6.9 mediumCVSS 4.0 · CNA: suse

Published2026-11-13Source updated 2026-11-13

Collected2026-11-132 attributed sources

Fixes and workarounds

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: CNA: suse

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
xorg-x11-server X.Org `xorg-x11-server`	≥ 0; < 21.1.26 (affected, rpm) Other versions: unaffected	CNA: suse
xwayland X.Org `xwayland`	≥ 0; < 24.1.15 (affected, rpm) Other versions: unaffected	CNA: suse

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
4.0 / 6.9 medium	`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N`	CNA: suse
4.0 / 6.9 medium	`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/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`	NVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

For agents and automation

Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.

Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.

Get an API key Use x402 Connect an agent

Endpoints and access details

https://api.y2.dev/api/v2/cyber/cves
https://api.y2.dev/api/v2/cyber/cves/{cveId}

A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.

For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.

Agent access JSON · OpenAPI · CVE API guide