Command Injection in TOTOLINK X5000R router with firmware v9.1.0u.6118_B20201102, and TOTOLINK A720R router with firmware v4.1.5cu.470_B20200911 allows remote attackers to execute arbitrary OS commands by sending a modified HTTP request. This occurs because the function executes glibc's system function with untrusted input. In the function, "command" parameter is directly passed to the attacker, allowing them to control the "command" field to attack the OS.