Backdoor is a software vulnerability or malware that allows an attacker to gain unauthorized access to a device. Backdoor allows an unauthorized user to use administrator rights and remotely administer the system: uninstall and install software, view and edit data, including encrypted data.
Backdoors are similar to regular utilities in many ways, but they have more functions. They not only allow an attacker to control processes at the operating system level, but also to make changes in Bios, turn the device on and off.