CVE-2021-47705

Published Dec 9, 2025 Modified Apr 15, 2026 CWE-787

Description

COMMAX UMS Client ActiveX Control 1.7.0.2 contains a heap-based buffer overflow vulnerability that allows attackers to execute arbitrary code by providing excessively long string arrays through multiple functions. Attackers can exploit improper boundary validation in CNC_Ctrl.dll to cause heap corruption and potentially gain system-level access.

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Weakness Type (CWE)

CWE-787 Out-of-bounds Write

References

Frequently Asked Questions

What is CVE-2021-47705? +
COMMAX UMS Client ActiveX Control 1.7.0.2 contains a heap-based buffer overflow vulnerability that allows attackers to execute arbitrary code by providing excessively long string arrays through multiple functions. Attackers can exploit improper boundary validation in CNC_Ctrl.dll to cause heap corruption and potentially gain system-level access.
How do I check if I'm vulnerable to CVE-2021-47705? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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