A critical stack-based buffer overflow vulnerability in Tenda i12 routers, specifically in version 1.0.0.6(2204), poses a significant risk of remote code execution.

This is a stack-based buffer overflow (CWE-121) caused by improper handling of the index argument within the formWifiMacFilterGet function. The vulnerability is remotely exploitable by an authenticated user, leading to potential memory corruption.

Successful exploitation of this buffer overflow could allow an attacker to gain unauthorized control over the affected network device. This severity, reflected by a CVSS score of 8.8, indicates a high risk of total system compromise, which could lead to unauthorized network access, data interception, or the use of the device as a pivot point for further attacks on the internal network.

Immediate Action: Since a specific patch is not currently identified, users should restrict administrative access to the device management interface to trusted IP addresses only and disable remote management features.

Proactive Monitoring: Monitor system logs for repeated failed authentication attempts or crashes associated with the /goform/WifiMacFilterGet endpoint.

Compensating Controls: Deploy a network firewall or Web Application Firewall (WAF) to inspect and block malformed HTTP requests targeting the identified function.

Public Exploit Available: Yes, a public proof-of-concept exists as documented in the research write-up at https://github.com/Jimi-Lab/cve/issues/2.

Given the availability of a public proof-of-concept and the potential for remote code execution, this vulnerability represents a high-priority risk. Administrators must immediately isolate the management interface of affected Tenda i12 units from the public internet and verify firmware update availability from the vendor to remediate the underlying code defect as soon as a patch is released.