ALAS2-2026-3894


Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-3894
Advisory Released Date: 2026-08-31
Advisory Updated Date: 2026-08-31
Severity: Important

Issue Overview:

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 as a result of 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 integer overflow. 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-2026-20339)

A vulnerability in the GPT file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device.

This vulnerability is due to improper handling of an endian conversion operation, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted GPT file 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-2026-20345)

A vulnerability in the PDF file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device.

This vulnerability is due to improper boundary checks for content in PDF files during scanning, which may result in an out-of-bounds buffer read. An attacker could exploit this vulnerability by submitting a crafted PDF file 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-2026-20346)

A vulnerability in the Mach-O file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device.

This vulnerability is due to improper boundary checks for content in Mach-O files during scanning, which may result in an out-of-bounds buffer read. An attacker could exploit this vulnerability by submitting a crafted Mach-O file 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-2026-20347)

A vulnerability in the XAR file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device.

This vulnerability is due to improper boundary checks for content in XAR files during scanning. An attacker could exploit this vulnerability by submitting a crafted file that contains XAR 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-2026-20348)


Affected Packages:

clamav1.4


Note:

This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.


Issue Correction:
Run yum update clamav1.4 or yum update --advisory ALAS2-2026-3894 to update your system.

New Packages:
aarch64:
    clamav1.4-1.4.6-1.amzn2.0.1.aarch64
    clamav1.4-lib-1.4.6-1.amzn2.0.1.aarch64
    clamav1.4-devel-1.4.6-1.amzn2.0.1.aarch64
    clamav1.4-freshclam-1.4.6-1.amzn2.0.1.aarch64
    clamd1.4-1.4.6-1.amzn2.0.1.aarch64
    clamav1.4-milter-1.4.6-1.amzn2.0.1.aarch64
    clamav1.4-debuginfo-1.4.6-1.amzn2.0.1.aarch64

noarch:
    clamav1.4-filesystem-1.4.6-1.amzn2.0.1.noarch
    clamav1.4-data-1.4.6-1.amzn2.0.1.noarch
    clamav1.4-doc-1.4.6-1.amzn2.0.1.noarch

src:
    clamav1.4-1.4.6-1.amzn2.0.1.src

x86_64:
    clamav1.4-1.4.6-1.amzn2.0.1.x86_64
    clamav1.4-lib-1.4.6-1.amzn2.0.1.x86_64
    clamav1.4-devel-1.4.6-1.amzn2.0.1.x86_64
    clamav1.4-freshclam-1.4.6-1.amzn2.0.1.x86_64
    clamd1.4-1.4.6-1.amzn2.0.1.x86_64
    clamav1.4-milter-1.4.6-1.amzn2.0.1.x86_64
    clamav1.4-debuginfo-1.4.6-1.amzn2.0.1.x86_64