CVE-2026-88806
📛 CVE Title
libX11 XkbGetMap Reply Heap-based Buffer Overflow
Description
A malicious X server could exploit a buffer overflow in libX11 before 1.8.14 during handling of XkbGetMap overflowing the key_sym_map.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- suse
- CVSS severity
- HIGH
- CVSS score
- 7.5 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H- Effective score
- 7.5 / 10 HIGH source: CNA overview
- MSRC score
- 7.5 / 10 HIGH MS rating: Important
- CWE(s)
-
CWE-122 - Reserved
- 2026-09-10
- Published
- 2026-09-21 13:42 UTC
- Last updated
- 2026-09-21 14:48 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/88xxx/CVE-2026-88806.json
- Linked Threat
- CVE-2026-88806 — libX11 XkbGetMap Reply Heap-based Buffer Overflow
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-21 14:17:22 UTC
- NVD last modified
- 2026-09-21 15:17:33 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: meissner@suse.de
- NVD CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H- Exploitability subscore
- 1.6 / 10
- Impact subscore
- 5.9 / 10
NVD / KEV / EPSS data refreshed 2026-09-22 03:24 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-83914 - Assigner
- suse
- Published
- Sep 21, 2026, 1:42:12 PM
- Updated
- Sep 22, 2026, 3:55:48 AM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.0000
- Vendors
- X.org
- Products
-
libX11 (0 <1.8.14)
- Aliases
-
GHSA-xrgw-w7v2-3qp8
ENISA description: A malicious X server could exploit a buffer overflow in libX11 before 1.8.14 during handling of XkbGetMap overflowing the key_sym_map.
EUVD references (1)
Microsoft Security Response Center MSRC
Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-09-26 03:08 UTC (source: CVRF).
- MS severity
- Important
- MS CVSS base score
- 7.5 / 10 (temporal 7.5)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - Release
- 2026-Sep
Microsoft remediations / KB articles (2)
- Release Notes — Vendor Fix / Security Update
- https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / Release Notes
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| x.org | libX11 |
0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (2)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- Vendor Fix msrc
- MSRC update guide: CVE-2026-88806 msrc
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://gitlab.freedesktop.org/xorg/lib/libx11/-/merge_requests/309 meissner@suse.de
Remediations (10)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.qualys.com
Executive Summary CVE - 2026 -68820 is an actively exploited Windows vulnerability listed in CISA's Known Exploited Vulnerabilities (KEV) Catalog, with a remediation deadline as suggested by CISA BOD 26-04. CISA BOD 26-04 introduces risk-based remediation timelines ranging from 3 to 14 days, increasing the pressure on teams to move quickly from patch availability to verified remediation ...
2026-09-22 16:46 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-09-22 16:46 UTC -
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-22 16:46 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-22 16:46 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-22 16:46 UTC -
web:support.servicenow.com
Due to additional analysis provided by the security researcher who discovered CVE - 2026 -6876, we have upgraded the severity rating of CVE - 2026 -6876 from High to Critical. This change affects only the severity
2026-09-22 16:46 UTC -
web:www.cisa.gov
CISA has added one new vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE - 2026 -85706 GitLab Community Edition and Enterprise Edition Path Traversal Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber ...
2026-09-22 16:46 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-09-22 16:46 UTC -
web:www.hivepro.com
Microsoft's August 2026 Patch Tuesday addresses 423 vulnerabilities including the actively exploited Windows AFD.sys zero-day CVE - 2026 -68820. Priority CVEs , patch guidance, and IOCs inside.
2026-09-22 16:46 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-22 16:46 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-88806.json.
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