TOTOLINK EX200 V4.0.3c.7646_B20201211 allows attackers to start the Telnet service without authorization via the telnet_enabled parameter in the setTelnetCfg function.
https://github.com/4hsien/CVE-vulns/blob/main/TOTOLINK/EX200/CI_5_setTelnetCfg/CI.md