CVE WatchAug 7, 2026

CVE-2026-20348

A vulnerability in the XAR file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly

CVSS

7.5

High

EPSS

—

KEV

—

Exploit Today

0-100

Published: Aug 7, 2026 · Last modified: Aug 7, 2026 · CWE-120

EPSS · 30d

Not enough EPSS history yet.

Technical description

A vulnerability in the XAR 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 XAR files during scanning. An attacker could exploit this vulnerability by submitting a crafted file that contains XAR content 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.

Official references

sec.cloudapps.cisco.comhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-clamav-WuuvVd26

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