#VU103240 Heap-based buffer overflow in ClamAV - CVE-2025-20128

Vulnerability identifier: #VU103240

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-20128

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
ClamAV
Client/Desktop applications / Antivirus software/Personal firewalls

Vendor: ClamAV

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error when decrypting OLE2 file format. A remote attacker can pass a specially crafted file to the application, trigger a heap-based buffer overflow and perform a denial of service (DoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

ClamAV: 1.0.0 - 1.0.7, 1.1.0, 1.1.1, 1.1.2, 1.1.3, 1.2.0 - 1.2.3, 1.3.0 - 1.3.2, 1.4.0 - 1.4.1

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External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-ole2-H549rphA

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.