DoS Vulnerability in ClamAV Due to ALZ File Format Parsing Issue
CVE-2026-20243

7.5HIGH

Key Information:

Vendor

Cisco
Status
Cisco Secure Endpoint
Vendor
CVE Published:
1 July 2026

Badges

👾 Exploit Exists

What is CVE-2026-20243?

A vulnerability exists in the ALZ file format parser of ClamAV, which can be exploited by an unauthenticated remote attacker to induce a Denial of Service (DoS) condition. This issue arises from inadequate boundary checks during the scanning of ALZ files, potentially leading to an out-of-bounds buffer write. An attacker could craft a malicious ALZ file and submit it for scanning, which may cause the ClamAV scanning process to terminate unexpectedly, disrupting services for users of affected systems.

Affected Version(s)

Cisco Secure Endpoint 7.0.5

Cisco Secure Endpoint 6.2.19

Cisco Secure Endpoint 7.3.3

References

https://sec.cloudapps.cisco.com/security/center/content/C...

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

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