CVE-2026-88806 - Vulnerability Details - OpenCVE

A malicious X server could exploit a buffer overflow in libX11 before 1.8.14 during handling of XkbGetMap overflowing the key_sym_map.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact total

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

x.org

libX11

unaffected

Version	Status	Constraints
`0`	affected	< 1.8.14

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

No data.

Project Subscriptions

Vendors	Products
X.org Subscribe	Libx11 Subscribe

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://gitlab.freedesktop.org/xorg/lib/libx11/-/merge_requests/309

History

Mon, 21 Sep 2026 15:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Mon, 21 Sep 2026 13:45:00 +0000

Type	Values Removed	Values Added
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.
Title		libX11 XkbGetMap Reply Heap-based Buffer Overflow
First Time appeared		X.org X.org libx11
Weaknesses		CWE-122
CPEs		cpe:2.3:a:x.org:libx11::::::::
Vendors & Products		X.org X.org libx11
References		https://gitlab.freedesktop.org/xorg/lib/libx11/-/merge_requests/309
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: suse

Published: 2026-09-21T13:42:12.700Z

Updated: 2026-09-21T14:48:16.632Z

Reserved: 2026-09-10T08:35:07.010Z

Link: CVE-2026-88806

Vulnrichment

Updated: 2026-09-21T14:39:41.457Z

NVD

Status : Received

Published: 2026-09-21T14:17:22.273

Modified: 2026-09-21T15:17:33.940

Link: CVE-2026-88806

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-09-21T15:30:16Z

Weaknesses

CWE-122

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