CVE-2021-47705 (GCVE-0-2021-47705)
Vulnerability from cvelistv5 – Published: 2025-12-09 20:37 – Updated: 2026-04-07 14:05
VLAI
EPSS
VEX
Title
CNC_Ctrl DllUnregisterServer Access Violation
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-09 21:35 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://www.exploit-db.com/exploits/50232 | exploit |
| https://www.zeroscience.mk/en/vulnerabilities/ZSL… | third-party-advisory |
| https://www.commax.com | technical-description |
| https://www.vulncheck.com/advisories/commax-ums-c… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| COMMAX Co., Ltd. | COMMAX UMS Client ActiveX Control |
Affected:
1.7.0.2
|
guessed |
Date Public
2021-08-27 00:00
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