NordVPN 3.3.10 for macOS suffers from a root privilege escalation vulnerability. The vulnerability stems from its privileged helper tool's implemented XPC service. This XPC service is responsible for receiving and processing new OpenVPN connection requests from the main application.

Unfortunately this XPC service is not protected, which allows arbitrary applications to connect and send it XPC messages. An attacker can send a crafted XPC message to the privileged helper tool requesting it make a new OpenVPN connection. Because he or she controls the contents of the XPC message, the attacker can specify the location of the openvpn executable, which could point to something malicious they control located on disk.

Without validation of the openvpn executable, this will give the attacker code execution in the context of the privileged helper tool.