Amazon Linux 2 : alsa-lib, --advisory ALAS2-2026-3874 (ALAS-2026-3874)

high Nessus Plugin ID 341887

Synopsis

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

Description

The version of alsa-lib installed on the remote host is prior to 1.1.4.1-2. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-3874 advisory.

The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read. (CVE-2026-56109)

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 alsa-lib' or or 'yum update --advisory ALAS2-2026-3874' to update your system.

Plugin Details

Severity: High

ID: 341887

File Name: al2_ALAS-2026-3874.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 8/31/2026

Updated: 8/31/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 3.5

Percentile: 51.69

CVSS v2

Risk Factor: Medium

Base Score: 5.6

Temporal Score: 4.1

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

CVSS Score Source: CVE-2026-56109

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.9

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

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

CVSS v4

Risk Factor: High

Base Score: 7

Threat Score: 4.7

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:alsa-lib-debuginfo, p-cpe:/a:amazon:linux:alsa-lib-devel, p-cpe:/a:amazon:linux:alsa-lib

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

Exploit Ease: No known exploits are available

Patch Publication Date: 8/31/2026

Vulnerability Publication Date: 6/22/2026

Reference Information

CVE: CVE-2026-56109

Detections

Analytics