Hackers can exfiltrate sensitive data stored in an IoT device such as Android smartphones. He/She abuses the Android pairing mode and targets a personal computer system previously trusted by the device user. The existing protocols that allow file transfer from Android IoT devices to the computer cannot detect this attack. In this paper, we propose an approach to detect attacks exploiting trusted relationship between a third party system such as personal computer and an Android device to exfiltrate user data from the victim device to an attacker. We implement a protocol to secure communication between IoT Android device and third party system. Our approach has been proved to be effective in detecting these category of attacks with reasonable performance overheads.