A critical stack-based buffer overflow in Tenda AX1803 firmware version 1.0.0.1 poses a severe risk of remote code execution or system denial of service.

The vulnerability exists in the formSetMacFilterCfg function located at the /goform/setMacFilterCfg endpoint. An authenticated attacker can supply a malicious deviceList parameter, which is copied into a stack buffer without adequate length validation, resulting in memory corruption.

Successful exploitation of this vulnerability allows an attacker to achieve remote code execution on the affected router. This could lead to full device compromise, unauthorized access to internal network traffic, and potential persistence for advanced persistent threats. Given the CVSS score of 8.8, this flaw represents a high risk to organizational network integrity and operational continuity.

Immediate Action: As no official patch is currently available, restrict access to the administrative interface and the /goform/setMacFilterCfg endpoint to trusted internal management networks only.

Proactive Monitoring: Monitor network traffic for unusual GET requests directed at the /goform/setMacFilterCfg endpoint, particularly those containing excessively long strings in the deviceList parameter.

Compensating Controls: Implement a Web Application Firewall (WAF) or equivalent network inspection rule to block requests containing anomalous payloads in the deviceList parameter.

Public Exploit Available: Yes, a published proof-of-concept exists, as documented in the researcher's GitHub repository.

Given the availability of a public proof-of-concept and the potential for remote code execution, this vulnerability should be treated with high priority. Network administrators must ensure the affected device is not exposed to the public internet and apply vendor-supplied firmware updates as soon as they become available to remediate the underlying memory corruption flaw.