RHEL 9 : xorg-x11-server (RHSA-2026:99122)

high Nessus Plugin ID 379420

Synopsis

The remote Red Hat host is missing a security update for xorg-x11-server.

Description

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:99122 advisory.

X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon.

Security Fix(es):

* xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL xorg-x11-server package based on the guidance in RHSA-2026:99122.

Plugin Details

Severity: High

ID: 379420

File Name: redhat-RHSA-2026-99122.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Red Hat Local Security Checks

Published: 11/12/2026

Updated: 11/12/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.38

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C

CVSS Score Source: CVE-2026-93520

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:rhel_eus:9.8, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-common, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-devel, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-source, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-xdmx, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-xephyr, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-xnest, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-xorg, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server-xvfb, p-cpe:/a:redhat:enterprise_linux:xorg-x11-server

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 11/12/2026

Vulnerability Publication Date: 10/7/2026

Reference Information

CVE: CVE-2026-93520

CWE: 787

RHSA: 2026:99122

Detections

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