Trojan.Agent refers to a generic Trojan malware detection. It is used for detections that are either associated with no specific malware families or not enough information is available to pinpoint the malware family.
Backdoor.Agent is a generic detection for backdoors that enable threat actors to gain remote access (and control) over an affected system.
Backdoors can be used to spy on the system’s user, and the threat actor can use the affected system for other malicious activities. For example, they can add the system to a botnet or use it to mine Bitcoins.
Malwarebytes protects users from Backdoor.Agent by using real-time protection.
Malwarebytes can detect and remove Backdoor.Agent without further user interaction. It is recommended to do a full system scan since this backdoor may have been used to install more malware onto the system.