Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: xorg-x11-server-Xwayland (UTSA-2026-147013)

high Nessus Plugin ID 373771

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-147013 advisory.

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. _XkbSetMapChecks() declares a fixed-size stack buffer mapWidths[256] indexed by key type index. The helper function CheckKeyTypes() writes to this buffer at a client-controlled offset, allowing a stack buffer overflow.
This may be used to crash the server, or for privilege escalation if the X server runs as root.

Tenable has extracted the preceding description block directly from the Unity 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 affected xorg-x11-server-Xwayland package.

See Also

https://access.redhat.com/errata/RHSA-2026:26562

https://access.redhat.com/errata/RHSA-2026:26566

https://access.redhat.com/errata/RHSA-2026:26590

https://access.redhat.com/errata/RHSA-2026:26610

https://access.redhat.com/errata/RHSA-2026:26709

https://access.redhat.com/errata/RHSA-2026:28923

https://access.redhat.com/errata/RHSA-2026:29844

https://access.redhat.com/errata/RHSA-2026:36083

https://access.redhat.com/errata/RHSA-2026:36085

https://access.redhat.com/errata/RHSA-2026:36086

https://access.redhat.com/errata/RHSA-2026:36087

https://access.redhat.com/errata/RHSA-2026:36632

https://access.redhat.com/errata/RHSA-2026:36633

https://access.redhat.com/errata/RHSA-2026:36634

https://access.redhat.com/errata/RHSA-2026:36768

https://access.redhat.com/errata/RHSA-2026:36791

https://access.redhat.com/errata/RHSA-2026:36792

https://access.redhat.com/errata/RHSA-2026:36798

https://access.redhat.com/errata/RHSA-2026:38502

https://access.redhat.com/errata/RHSA-2026:38810

https://access.redhat.com/errata/RHSA-2026:46377

https://access.redhat.com/errata/RHSA-2026:46382

https://access.redhat.com/errata/RHSA-2026:46385

https://access.redhat.com/errata/RHSA-2026:46392

https://access.redhat.com/errata/RHSA-2026:46456

https://access.redhat.com/errata/RHSA-2026:46460

https://access.redhat.com/errata/RHSA-2026:46473

https://access.redhat.com/errata/RHSA-2026:49519

https://access.redhat.com/security/cve/CVE-2026-50259

https://bugzilla.redhat.com/show_bug.cgi?id=2485384

https://lists.x.org/archives/xorg-announce/2026-June/003702.html

https://redhat.atlassian.net/browse/PSIRTSUPT-16950

http://www.nessus.org/u?226ecd14

http://www.nessus.org/u?edd5fb54

Plugin Details

Severity: High

ID: 373771

File Name: unity_linux_UTSA-2026-147013.nasl

Version: 1.1

Type: Local

Published: 10/29/2026

Updated: 10/29/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 57.98

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-2026-50259

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

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

Exploit Ease: No known exploits are available

Patch Publication Date: 10/30/2026

Vulnerability Publication Date: 6/1/2026

Reference Information

CVE: CVE-2026-50259