Denial of Service Vulnerability in ClamAV's HTML Cascading Style Sheets Module
CVE-2026-20031

5.3MEDIUM

Key Information:

Vendor

Cisco
Status
Cisco Secure Endpoint
Vendor
CVE Published:
4 March 2026

Badges

👾 Exploit Exists

What is CVE-2026-20031?

A vulnerability exists in the HTML Cascading Style Sheets (CSS) module of ClamAV, enabling an unauthenticated remote attacker to induce a denial of service (DoS) on affected devices. The flaw arises from improper error handling during the process of splitting UTF-8 strings. By submitting a specifically crafted HTML file for scanning, an attacker can disrupt the scanning process, thereby compromising the availability of the service. This presents a potential risk for systems relying on ClamAV for malware protection.

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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:
5.3
Severity:
MEDIUM
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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