CVE-2021-47719 HIGH

CVE-2021-47719: CNC_Ctrl DllUnregisterServer f5501 Access Violation

Vendor Commax Co., Ltd.
Product COMMAX WebViewer ActiveX Control
Weakness CWE-787
Published December 9, 2025
Last update April 7, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

COMMAX WebViewer ActiveX Control 2.1.4.5 contains a buffer overflow vulnerability that allows attackers to execute arbitrary code by providing excessively long string arrays through multiple functions. Attackers can exploit boundary errors in Commax_WebViewer.ocx to cause buffer overflow conditions and potentially gain code execution.

Key dates

02Disclosure timeline

December 9, 2025 CVE published
April 7, 2026 Record updated