A critical stack-based buffer overflow vulnerability in Tenda W3 firmware (version 1.0.0.3(2204)) may allow remote attackers to execute arbitrary code or cause a denial of service.

This vulnerability is a stack-based buffer overflow (CWE-121) located in the formWifiMacFilterSet function within the /goform/WifiMacFilterSet endpoint. An attacker with low-level privileges can trigger this flaw by sending a specially crafted POST request containing an oversized GO parameter, leading to memory corruption.

Successful exploitation of this vulnerability could lead to total system compromise, allowing an attacker to execute arbitrary code or crash the affected networking device. Given the CVSS score of 8.8, this represents a high-severity risk that could result in unauthorized network access, data interception, or sustained denial of service for critical infrastructure relying on the Tenda W3 hardware.

Immediate Action: Since no official patch is currently available, administrators should restrict network access to the management interface of the Tenda W3 device to trusted internal management segments only.

Proactive Monitoring: Monitor system logs for repeated crash events or unauthorized POST requests directed at the /goform/WifiMacFilterSet endpoint.

Compensating Controls: Implement a Web Application Firewall or network-level access control list to block traffic to the vulnerable /goform/WifiMacFilterSet URI from untrusted sources.

Public Exploit Available: Yes, a proof-of-concept exists as documented in the GitHub research repository linked by the CVE record.

The presence of a public proof-of-concept combined with the critical nature of a memory corruption flaw necessitates immediate defensive action. Organizations using the affected Tenda W3 firmware should prioritize isolating these devices from the public internet and restricting access to the management interface until the vendor releases a security update.