COMMAX UMS Client ActiveX Control 1.7.0.2 CNC_Ctrl.dll out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k0.00

Summaryinfo

A vulnerability was found in COMMAX UMS Client ActiveX Control 1.7.0.2. It has been classified as critical. This affects an unknown part in the library CNC_Ctrl.dll. This manipulation causes out-of-bounds write. This vulnerability is tracked as CVE-2021-47705. The attack is possible to be carried out remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability classified as critical was found in COMMAX UMS Client ActiveX Control 1.7.0.2. Affected by this vulnerability is an unknown code block in the library CNC_Ctrl.dll. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was disclosed by Gjoko Krstic as 50232. The advisory is shared at exploit-db.com. This vulnerability is known as CVE-2021-47705 since 12/05/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details and also a public exploit are known.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (50232). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Exploit-DB: 🔒

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

12/05/2025 CVE reserved
12/10/2025 +5 days Advisory disclosed
12/10/2025 +0 days VulDB entry created
12/10/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: 50232
Researcher: Gjoko Krstic
Status: Not defined

CVE: CVE-2021-47705 (🔒)
GCVE (CVE): GCVE-0-2021-47705
GCVE (VulDB): GCVE-100-335557
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 12/10/2025 08:05
Changes: 12/10/2025 08:05 (71)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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