CVE-2025-20234
highpriority · track · 30EPSS 0.008 · 57 %ileDEEURUUSEPSS · scored 2026-10-27
A vulnerability in Universal Disk Format (UDF) processing 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 a memory overread during UDF file scanning. An attacker could exploit this vulnerability by submitting a crafted file containing UDF 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 .
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Secure Endpointcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.3–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (100)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2025-1362ClamAV: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2025-06-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in ClamAV ausnutzen, um einen Denial of Service Angriff durchzuführen.
- cisco-sa-clamav-udf-hmwd9nDyClamAV UDF File Parsing Out-of-Bounds Read Information Disclosure Vulnerability2025-06-18csaf · cisco_csafUS
A vulnerability in Universal Disk Format (UDF) processing 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 a memory overread during UDF file scanning. An attacker could exploit this vulnerability by submitting a crafted file containing UDF 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 ClamAV blog ["https://blog.clamav.net/2025/06/clamav-143-and-109-security-patch.html"]. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2025-20234cnnvd
- https://blog.clamav.net/2025/06/clamav-143-and-109-security-patch.htmlcnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-udf-hmwd9nDycnnvd
- https://vigilance.fr/vulnerability/ClamAV-out-of-bounds-memory-reading-via-UDF-File-Parser-47473cnnvd
- https://blog.clamav.net/2025/06/clamav-143-and-109-security-patch.htmlenisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-udf-hmwd9nDyenisa_euvd
- https://blog.clamav.net/2025/06/clamav-143-and-109-security-patch.htmlVendor Advisorynvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-udf-hmwd9nDyThird Party Advisorynvd
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