CVE-2025-20128: clamav Heap Overflow — Fix

Description

A vulnerability in the Object Linking and Embedding 2 (OLE2) decryption routine of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an integer underflow in a bounds check that allows for a heap buffer overflow read. An attacker could exploit this vulnerability by submitting a crafted file containing OLE2 content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to terminate the ClamAV scanning process, resulting in a DoS condition on the affected software. For a description of this vulnerability, see the . Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weakness Type (CWE)

CWE-122 CWE-122

Affected Products

Vendor	Product	Versions
clamav	clamav	1.0.0 — 1.0.8
clamav	clamav	1.1.0 — 1.4.2
cisco	secure_endpoint	< 1.24.4
cisco	secure_endpoint	< 1.25.1
cisco	secure_endpoint	< 7.5.20
cisco	secure_endpoint	8.0.1.21160 — 8.4.3
cisco	secure_endpoint_private_cloud	< 4.2.0

References

Advisories & Patches

https://blog.clamav.net/2025/01/clamav-142-and-108-security-patch.html

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-ole2-H549rphA https://lists.debian.org/debian-lts-announce/2025/09/msg00006.html

Frequently Asked Questions

What is CVE-2025-20128? +

A vulnerability in the Object Linking and Embedding 2 (OLE2) decryption routine of ClamAV could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an integer underflow in a bounds check that allows for a heap buffer overflow read. An attacker could exploit this vulnerability by submitting a crafted file containing OLE2 content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to terminate the ClamAV scanning process, resulting in a DoS condition on the affected software. For a description of this vulnerability, see the . Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2025-20128? +

CVE-2025-20128 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-20128? +

CVE-2025-20128 affects products from cisco, clamav, specifically: clamav, secure_endpoint, secure_endpoint_private_cloud. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-20128? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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