Tenda W6_S v1.0.0.4_510 has a Buffer Overflow vulnerability in the setcfm function, which allows remote attackers to cause web server crash via parameter funcpara1 passed to the binary through a POST request.
https://github.com/IdaJea/IOT_vuln_1/blob/master/w6_s_v1.0.0.4/setcfm.pdf