A critical stack-based buffer overflow vulnerability in Tenda WH450 firmware allows unauthenticated remote attackers to achieve arbitrary code execution or cause a denial of service.

The vulnerability is a stack-based buffer overflow located in the HTTP request handler for the /goform/CheckTools endpoint. An unauthenticated attacker can trigger this condition by supplying an excessively long string to the ipaddress parameter, leading to memory corruption.

The vulnerability carries a CVSS score of 9.8, indicating a critical risk to organizational infrastructure. Successful exploitation allows an attacker to gain full control over the router, potentially leading to complete compromise of network traffic, unauthorized internal access, or total system unavailability.

Immediate Action: As no patch is currently available, administrators should immediately restrict access to the device management interface by placing it behind a firewall or disabling remote management features entirely.

Proactive Monitoring: Monitor network traffic for anomalous HTTP GET requests directed at the /goform/CheckTools path, specifically looking for requests containing unusually long query parameters.

Compensating Controls: Implement a Web Application Firewall (WAF) rule to drop or sanitize incoming requests that contain oversized ipaddress parameters.

Public Exploit Available: Yes, a proof-of-concept script and reproduction details are available via the security researcher's write-up on GitHub.

Given the critical severity and the public availability of exploit code, this vulnerability poses a severe risk to any exposed Tenda WH450 device. Organizations should verify if their hardware is reachable from the internet and take immediate steps to isolate these devices from external access until the manufacturer releases a firmware update to resolve the memory corruption flaw.