Detections
Analytics

AlmaLinux 9 : xorg-x11-server-Xwayland (ALSA-2026:38490)

critical Nessus Plugin ID 334947

Synopsis

The remote AlmaLinux host is missing one or more security updates.

Description

The remote AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:38490 advisory.

 * xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow (CVE-2026-55999)
 * X.org: xorg-x11-server: GLX contextTags Use-After-Free in CommonMakeCurrent() (CVE-2026-56000)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

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

Solution

Update the affected xorg-x11-server-Xwayland and / or xorg-x11-server-Xwayland-devel packages.

See Also

https://access.redhat.com/errata/RHSA-2026:38490

https://errata.almalinux.org/9/ALSA-2026-38490.html

Plugin Details

Severity: Critical

ID: 334947

File Name: alma_linux_ALSA-2026-38490.nasl

Version: 1.1

Type: Local

Published: 8/12/2026

Updated: 8/12/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.1

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-2026-56000

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

CVSS v4

Risk Factor: Critical

Base Score: 9

Threat Score: 6.1

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Vulnerability Information

CPE: cpe:/o:alma:linux:9, cpe:/o:alma:linux:9::appstream, cpe:/o:alma:linux:9::baseos, cpe:/o:alma:linux:9::crb, cpe:/o:alma:linux:9::highavailability, cpe:/o:alma:linux:9::nfv, cpe:/o:alma:linux:9::realtime, cpe:/o:alma:linux:9::resilientstorage, cpe:/o:alma:linux:9::sap, cpe:/o:alma:linux:9::sap_hana, cpe:/o:alma:linux:9::supplementary, p-cpe:/a:alma:linux:xorg-x11-server-xwayland-devel, p-cpe:/a:alma:linux:xorg-x11-server-xwayland

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

Exploit Ease: No known exploits are available

Patch Publication Date: 7/13/2026

Vulnerability Publication Date: 7/8/2026

Reference Information

CVE: CVE-2026-55999, CVE-2026-56000

CWE: 805, 825

RHSA: 2026:38490