RHEL 9 : libxml2 (RHSA-2026:71585)

high Nessus Plugin ID 349918

Synopsis

The remote Red Hat host is missing one or more security updates for libxml2.

Description

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:71585 advisory.

The libxml2 library is a development toolbox providing the implementation of various XML standards.

Security Fix(es):

* libxml2: libxml2: Arbitrary code execution via heap-based buffer overflow (CVE-2026-86138)

* libxml2: libxml2: Data integrity issues due to integer overflow in write callbacks (CVE-2026-86143)

* libxml2: libxml2: Arbitrary code execution via stack-based buffer overflow in xmlSnprintfElements (CVE-2026-86140)

* libxml2: libxml2: Heap-based buffer overflow in xmlXPtrEval due to xpointer length saturation (CVE-2026-86142)

* libxml2: libxml2: Information disclosure, SSRF, or denial of service due to improper parseFlags propagation. (CVE-2026-86144)

* libxml2: double-free/UAF in libxml2 Python bindings (CVE-2026-74860)

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 these issues but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL libxml2 package based on the guidance in RHSA-2026:71585.

See Also

https://access.redhat.com/errata/RHSA-2026:71585

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=2528986

https://bugzilla.redhat.com/show_bug.cgi?id=2528987

https://bugzilla.redhat.com/show_bug.cgi?id=2528989

https://bugzilla.redhat.com/show_bug.cgi?id=2528990

https://bugzilla.redhat.com/show_bug.cgi?id=2528992

https://bugzilla.redhat.com/show_bug.cgi?id=2529697

http://www.nessus.org/u?d035a5a0

Plugin Details

Severity: High

ID: 349918

File Name: redhat-RHSA-2026-71585.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 9/24/2026

Updated: 9/24/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.43

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2026-86144

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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:P/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:9, cpe:/o:redhat:rhel_eus:9.8, p-cpe:/a:redhat:enterprise_linux:libxml2-devel, p-cpe:/a:redhat:enterprise_linux:libxml2, p-cpe:/a:redhat:enterprise_linux:python3-libxml2

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 9/24/2026

Vulnerability Publication Date: 9/5/2026

Reference Information

CVE: CVE-2026-74860, CVE-2026-86138, CVE-2026-86140, CVE-2026-86142, CVE-2026-86143, CVE-2026-86144

CWE: 120, 190, 192, 669, 763, 805

RHSA: 2026:71585