Attackers can exploit known vulnerabilities to infiltrate a device's firmware and the communication between firmware binaries, in order to pass between them. To improve cybersecurity, organizations must identify and mitigate the risks of the firmware they use. An attack graph (AG) can be used to assess and visually display firmware's risks by organizing the identified vulnerabilities into attack paths composed of sequences of actions attackers may perform to compromise firmware images. In this paper, we utilize AGs for firmware risk assessment. We propose MIRAGE (Multi-binary Image Risk Assessment with Attack Graph Employment), a framework for identifying potential attack vectors and vulnerable interactions between firmware binaries; MIRAGE accomplishes this by generating AGs for firmware inter-binary communication. The use cases of the proposed firmware AG generation framework include the identification of risky external interactions, supply chain risk assessment, and security analysis with digital twins. To evaluate the MIRAGE framework, we collected a dataset of 703 firmware images. We also propose a model for examining the risks of firmware binaries, demonstrate the model's implementation on the dataset of firmware images, and list the riskiest binaries.