RHEL 9 : libX11 (RHSA-2026:98461)

high Nessus Plugin ID 379084

Synopsis

The remote Red Hat host is missing a security update for libX11.

Description

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:98461 advisory.

The libX11 packages contain the core X11 protocol client library.

Security Fix(es):

* libX11: libX11: Heap-based buffer overflow via malicious X server (CVE-2026-88806)

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 libX11 package based on the guidance in RHSA-2026:98461.

Plugin Details

Severity: High

ID: 379084

File Name: redhat-RHSA-2026-98461.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Red Hat Local Security Checks

Published: 11/11/2026

Updated: 11/11/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.6

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 5.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-88806

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/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:enterprise_linux:9, p-cpe:/a:redhat:enterprise_linux:libx11-common, p-cpe:/a:redhat:enterprise_linux:libx11-devel, p-cpe:/a:redhat:enterprise_linux:libx11-xcb, p-cpe:/a:redhat:enterprise_linux:libx11

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: 11/11/2026

Vulnerability Publication Date: 9/21/2026

Reference Information

CVE: CVE-2026-88806

CWE: 787

RHSA: 2026:98461

Detections

Analytics