CVE-2022-46531

Vulnerability

A buffer overflow vulnerability exists in the Tenda F1203 router firmware version V2.0.1.6, specifically in the addWifiMacFilter function of the httpd module. The overflow is triggered through the deviceId parameter when handling a POST request to the /goform/addWifiMacFilter endpoint. The affected firmware version is V2.0.1.6, and the manufacturer is Tenda [1].

Exploitation

An attacker can exploit this vulnerability by sending a crafted HTTP POST request to the /goform/addWifiMacFilter endpoint with an overly long deviceId parameter. No authentication is required beyond an existing session (as demonstrated by the POC using a valid user=admin cookie). The provided POC includes a 4111-byte deviceId value, which causes a buffer overflow [1].

Impact

Successful exploitation results in a denial of service (DoS) condition, as demonstrated by the POC. The overflow likely corrupts adjacent memory, crashing the httpd process and rendering the router's web interface temporarily unavailable. No code execution or data disclosure is indicated by the available references [1].

Mitigation

As of the reference publication (December 2022), no fix or updated firmware version has been released by Tenda. The vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog as of the current date. The affected firmware can be downloaded from Tenda's support page [1]. Users should monitor the vendor's website for any security updates or consider isolating the router's management interface from untrusted network segments.