CVE-2021-47719 (GCVE-0-2021-47719)
Vulnerability from cvelistv5 – Published: 2025-12-09 20:41 – Updated: 2026-04-07 14:05
VLAI
EPSS
VEX
Title
CNC_Ctrl DllUnregisterServer f5501 Access Violation
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-12 16:45 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://www.exploit-db.com/exploits/50231 | exploit |
| https://www.zeroscience.mk/en/vulnerabilities/ZSL… | third-party-advisory |
| https://www.commax.com | product |
| https://www.vulncheck.com/advisories/commax-webvi… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| COMMAX Co., Ltd. | COMMAX WebViewer ActiveX Control |
Affected:
2.1.4.5
|
guessed |
Date Public
2021-08-27 00:00
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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