Bug 2496096 (CVE-2026-20214)

Summary: CVE-2026-20214 clamav: ClamAV: Denial of Service via crafted FSG file parsing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in ClamAV. An unauthenticated, remote attacker could exploit a vulnerability in the FSG file format parser by submitting a specially crafted file for scanning. This improper handling of FSG files can lead to an out-of-bounds buffer write, causing memory corruption. A successful exploit results in a Denial of Service (DoS) condition, terminating the ClamAV scanning process.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2496834, 2496835    
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Description OSIDB Bzimport 2026-07-01 18:02:17 UTC 
A vulnerability in the FSG file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected device.

This vulnerability is due to improper boundary checks for content in FSG files during scanning, which may result in an out-of-bounds buffer write. An attacker could exploit this vulnerability by submitting a crafted file that contains portable executable content compressed with FSG 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.