Amazon Linux 2 : libxml2 (ALAS-2026-4059)

medium Nessus Plugin ID 374391

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of libxml2 installed on the remote host is prior to 2.9.1-6. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-4059 advisory.

A flaw was found in libxml2. A local user or an attacker providing a specially crafted XML catalog can trigger a NULL pointer dereference during XML catalog parsing. This occurs when a `nextCatalog` element lacks its mandatory `catalog` attribute, leading to the application crashing and causing a Denial of Service (DoS). (CVE-2026-76781)

Tenable has extracted the preceding description block directly from the tested product 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

Run 'yum update libxml2' or or 'yum update --advisory ALAS2-2026-4059' to update your system.

Plugin Details

Severity: Medium

ID: 374391

File Name: al2_ALAS-2026-4059.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 10/30/2026

Updated: 10/30/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.58

CVSS v2

Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

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

CVSS Score Source: CVE-2026-76781

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:libxml2-debuginfo, p-cpe:/a:amazon:linux:libxml2-devel, p-cpe:/a:amazon:linux:libxml2-python, p-cpe:/a:amazon:linux:libxml2-static, p-cpe:/a:amazon:linux:libxml2

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

Exploit Ease: No known exploits are available

Patch Publication Date: 10/30/2026

Vulnerability Publication Date: 9/17/2026

Reference Information

CVE: CVE-2026-76781

Detections

Analytics