Amazon Linux 2023 : clamav1.4, clamav1.4-data, clamav1.4-devel (ALAS2023-2026-1956)

high Nessus Plugin ID 328497

Synopsis

The remote Amazon Linux 2023 host is missing a security update.

Description

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1956 advisory.

A vulnerability in the PE file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.This vulnerability is due to improper boundary checks for content in PE files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains PE content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20213)

A vulnerability in the FSG file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.This vulnerability is due to improper boundary checks for content in FSG files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains portable executable content compressed with FSG to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20214)

A vulnerability in the 7z file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.This vulnerability is due to improper boundary checks for content in 7z files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains 7zcontent to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20215)

A vulnerability in the InstallShield file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device.This vulnerability is due to improper handling of temporary resources during file scanning. An attacker could exploit this vulnerability by submitting a crafted InstallShield file to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to terminate the ClamAV scanning process and temporarily consume available system resources, resulting in a DoS condition on the affected software. (CVE-2026-20216)

A vulnerability in the PESpin file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.This vulnerability is due to improper boundary checks for content in PESpin files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains PESpin content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20217)

A vulnerability in the ALZ file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.This vulnerability is due to improper boundary checks for content in ALZ files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains ALZ content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software. (CVE-2026-20243)

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

Run 'dnf update clamav1.4 --releasever 2023.12.20260720' or or 'dnf update --advisory ALAS2023-2026-1956 --releasever 2023.12.20260720' to update your system.

Plugin Details

Severity: High

ID: 328497

File Name: al2023_ALAS2023-2026-1956.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 7/20/2026

Updated: 7/20/2026

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: 23.77

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-20243

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/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:2023, p-cpe:/a:amazon:linux:clamav1.4-data, p-cpe:/a:amazon:linux:clamav1.4-debuginfo, p-cpe:/a:amazon:linux:clamav1.4-debugsource, p-cpe:/a:amazon:linux:clamav1.4-devel, p-cpe:/a:amazon:linux:clamav1.4-doc, p-cpe:/a:amazon:linux:clamav1.4-filesystem, p-cpe:/a:amazon:linux:clamav1.4-freshclam-debuginfo, p-cpe:/a:amazon:linux:clamav1.4-freshclam, p-cpe:/a:amazon:linux:clamav1.4-lib-debuginfo, p-cpe:/a:amazon:linux:clamav1.4-lib, p-cpe:/a:amazon:linux:clamav1.4-milter-debuginfo, p-cpe:/a:amazon:linux:clamav1.4-milter, p-cpe:/a:amazon:linux:clamav1.4, p-cpe:/a:amazon:linux:clamd1.4-debuginfo, p-cpe:/a:amazon:linux:clamd1.4

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

Exploit Ease: No known exploits are available

Patch Publication Date: 7/20/2026

Vulnerability Publication Date: 7/1/2026

Reference Information

CVE: CVE-2026-20213, CVE-2026-20214, CVE-2026-20215, CVE-2026-20216, CVE-2026-20217, CVE-2026-20243

IAVA: 2026-A-0653

Detections

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