ClamAV PDF file format parser out-of-bounds

Summaryinfo

A vulnerability, which was classified as critical, has been found in ClamAV. Affected is an unknown function of the component PDF file format parser. Performing a manipulation results in out-of-bounds. This vulnerability is known as CVE-2026-20346. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical has been found in ClamAV (affected version unknown). This affects an unknown functionality of the component PDF file format parser. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at sec.cloudapps.cisco.com. This vulnerability is uniquely identified as CVE-2026-20346 since 10/08/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 333533 (Linux Distros Unpatched Vulnerability : CVE-2026-20346), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (333533), EUVD (EUVD-2026-54530) and CERT Bund (WID-SEC-2026-2708). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Open Source ClamAV
• Cisco Secure Endpoint

Productinfo

Type

• Anti-Malware Software

Name

• ClamAV

License

• free

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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