CentOS Linux 7 [TuxCare] Security Update: xorg-x11-server-Xdmx / xorg-x11-server-Xephyr / etc Multiple Vulnerabilities (CENTOS7:CLSA-2026:1793374616)

high Nessus Plugin ID 375668

Synopsis

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

Description

The CentOS Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the TuxCare CENTOS7:CLSA-2026:1793374616 advisory.

- A use-after-free caused by lack of lifecycle management when adding / removing XInput master devices in X.org X Server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X Clients to crash the X server or potentially execute code in X server context. (CVE-2026-93516)

- A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context. (CVE-2026-93517)

- An integer truncation issue in XkbResizeKeyType() that could lead to a heap buffer overflow by authenticated X clients in X.org X server before 21.1.25 and XWayland before 24.1.14 could be exploited for crashes or potential code execution in the X server. (CVE-2026-93518)

- A buffer overflow when handling pointer barriers in the XFIXES extension in X.Org X server before 21.1.25 and XWayland before 24.1.14 could be used by authenticated X clients to crash or potentially execute code in X server context. (CVE-2026-93519)

- A buffer overflow in RandR ChangeProviderProperty requests in X.Org X Server before 2.1.25 and XWayland before 24.4.14 could be used by authenticated X clients to crash or execute code within the X server context. (CVE-2026-93521)

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 packages based on the guidance in TuxCare advisory CENTOS7:CLSA-2026:1793374616.

See Also

https://cve.tuxcare.com/els/releases/CLSA-2026:1793374616

http://www.nessus.org/u?54019244

Plugin Details

Severity: High

ID: 375668

File Name: tuxcare_centos_7_CLSA-2026-1793374616.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 11/3/2026

Updated: 11/3/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.38

Vendor

Vendor Severity: Important

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-2026-93521

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: High

Base Score: 8.5

Threat Score: 5.9

Threat Vector: CVSS:4.0/E:U

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

CVSS Score Source: CVE-2026-93517

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list, Host/OS/extended-third-party

Exploit Ease: No known exploits are available

Patch Publication Date: 10/30/2026

Vulnerability Publication Date: 10/7/2026

Reference Information

CVE: CVE-2026-93516, CVE-2026-93517, CVE-2026-93518, CVE-2026-93519, CVE-2026-93521

CLSA: 2026:1793374616