CVE-2025-20260 ClamAV PDF Scanning Buffer Overflow Vulnerability

Critical 9.8 Published 18 Jun 2025 Updated 26 Feb 2026

Remote attackers can cause denial of service or potentially execute arbitrary code via crafted PDF files processed by ClamAV.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2025-20260?

CVE-2025-20260 is a critical memory corruption vulnerability in Clamav Clamav, published on 18 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability in the PDF scanning processes of ClamAV could allow an unauthenticated, remote attacker to cause a buffer overflow condition, cause a denial of service (DoS) condition, or execute arbitrary code on an affected device. This vulnerability exists because memory buffers are allocated incorrectly when PDF files are processed. 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 trigger a buffer overflow, likely resulting in the termination of the ClamAV scanning process and a DoS condition on the affected software. Although unproven, there is also a possibility that an attacker could leverage the buffer overflow to execute arbitrary code with the privileges of the ClamAV process.

Weakness: CWE-122

Which versions are affected by CVE-2025-20260?

It affects 1 product.

Products include Clamav Clamav.

How do I fix CVE-2025-20260?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2025-20260 being exploited?

There is no known exploitation of CVE-2025-20260 in the wild and no public exploit code.

Public exploit code: 2 proofs of concept on GitHub.

All Clamav Clamav vulnerabilities

Sources

Also known as AZL-64208, AZL-64223, DEBIAN-CVE-2025-20260, GHSA-596c-w2jc-jmmx, MGASA-2025-0190, MINI-fhjj-4mmh-hh4p and 6 more.