CVE-2021-47709
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-12-09

Last updated on: 2025-12-09

Assigner: VulnCheck

Description
COMMAX Smart Home System allows an unauthenticated attacker to change configuration and cause denial-of-service through the setconf endpoint. Attackers can trigger a denial-of-service scenario by sending a malformed request to the setconf endpoint.
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Meta Information
Published
2025-12-09
Last Modified
2025-12-09
Generated
2026-06-16
AI Q&A
2025-12-09
EPSS Evaluated
2026-06-15
NVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
commax smart_home_system 4.0
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-306 The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
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Executive Summary

This vulnerability in the COMMAX Smart Home System allows an unauthenticated attacker to change the system configuration and cause a denial-of-service by sending a malformed request to the setconf endpoint.

Detection Guidance

This vulnerability can be detected by monitoring for unauthorized or malformed HTTP POST requests sent to the '/goform/setconf' endpoint on the COMMAX Smart Home Ruvie CCTV Bridge DVR Service. Specifically, look for POST requests with parameters like 'manufacturer', 'Ch0', 'dvr0', or other configuration parameters being changed without authentication. Network traffic analysis tools such as tcpdump or Wireshark can be used to capture such requests. For example, a command to capture HTTP POST requests to the setconf endpoint could be: tcpdump -i <interface> -A 'tcp port 80 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)' | grep '/goform/setconf'. Additionally, checking device logs for unexpected configuration changes or restarts within short intervals may indicate exploitation attempts. [4]

Mitigation Strategies

Immediate mitigation steps include restricting network access to the vulnerable device, especially blocking external or untrusted network access to the '/goform/setconf' endpoint. Implement network-level controls such as firewall rules to prevent unauthorized HTTP POST requests to this endpoint. If possible, isolate the device on a separate VLAN or network segment. Monitor the device for unusual restarts or configuration changes. Since the device lacks authentication on this critical function, applying any available firmware updates or patches from the vendor is recommended, although no response from the vendor was noted. If no patch is available, consider disabling the vulnerable service or replacing the device to prevent exploitation. [1, 3, 4]

Impact Analysis

An attacker can exploit this vulnerability to disrupt the normal operation of the COMMAX Smart Home System by causing a denial-of-service, potentially making the system unavailable or unstable. Additionally, unauthorized configuration changes could compromise the system's intended functionality.

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