CVE-2022-46542

Vulnerability

A buffer overflow vulnerability exists in the fromAddressNat function of Tenda F1203 router firmware version V2.0.1.6. The flaw is triggered via a crafted POST request to /goform/addressNat with an overly long page parameter. This handling occurs in the httpd module and requires no authentication, as the router's web interface exposes this endpoint without proper bounds checking [1].

Exploitation

An attacker can exploit this vulnerability by sending a POST request to the target router's /goform/addressNat endpoint with a page parameter containing a large buffer of characters (e.g., 4106 'a' characters). The request can be made from the local network without prior authentication. No user interaction is needed beyond the attacker sending the malicious request [1].

Impact

Successful exploitation leads to a buffer overflow that causes the httpd process to crash, resulting in a denial of service (DoS) condition. The router may become unresponsive until restarted. The impact is limited to service disruption, as the provided proof-of-concept only demonstrates a crash and not arbitrary code execution [1].

Mitigation

As of the publication date (2022-12-20), no official patch has been released by Tenda for this vulnerability. Users should monitor Tenda's firmware update page for future fixes. Until a patch is available, limiting access to the router's web interface from untrusted networks can reduce exposure [1].