CVE WatchAug 7, 2026

CVE-2026-20337

A vulnerability in the zip archive parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition on an affected

CVSS

7.5

High

EPSS

—

KEV

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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 zip archive parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device. This vulnerability is due to improper boundary checks for content in zip files during scanning, which may result in an out-of-bounds write condition. An attacker could exploit this vulnerability by submitting a crafted zip file for scanning. 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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