A critical stack-based buffer overflow vulnerability in Tenda AC15 firmware exposes affected devices to remote code execution and potential system compromise.

The flaw exists within the formSetCfm function of the /goform/setcfm file, where improper handling of the funcpara1 argument during a POST request leads to a stack-based buffer overflow. While the CVSS vector indicates low privileges are required, the vulnerability is remotely exploitable and allows for memory corruption.

A successful exploit of this vulnerability could allow an attacker to achieve remote code execution, potentially leading to a full compromise of the networking device. Given the CVSS score of 8.8, this represents a high-severity risk that could facilitate unauthorized network access, interception of traffic, or the use of the device as a pivot point for further lateral movement within the corporate environment.

Immediate Action: Since no official patch is currently available, administrators should restrict network access to the management interface of the Tenda AC15 to trusted IP addresses only.

Proactive Monitoring: Monitor device logs for unusual POST requests directed at the /goform/setcfm endpoint and watch for signs of abnormal device behavior or unexpected restarts.

Compensating Controls: Deploy a Web Application Firewall (WAF) or an Intrusion Prevention System (IPS) rule to inspect and block malicious payloads targeting the funcpara1 argument in HTTP POST requests.

Public Exploit Available: Yes — a published proof-of-concept exists, as documented in the researcher write-up referenced in the vulnerability disclosure.

Due to the severity of this memory corruption flaw and the existence of public proof-of-concept material, immediate defensive action is required. Organizations utilizing Tenda AC15 devices must isolate them from the public internet and implement strict access controls until the vendor releases a security update addressing the buffer overflow.