A physical attack vulnerability exists in certain Moxa industrial computers using TPM-backed LUKS full-disk encryption on Moxa Industrial Linux 3, where the discrete TPM is connected to the CPU via an SPI bus. Exploitation requires invasive physical access, including opening the device and attaching external equipment to the SPI bus to capture TPM communications. If successful, the captured data may allow offline decryption of eMMC contents. This attack cannot be performed through brief or opportunistic physical access and requires extended physical access, possession of the device, appropriate equipment, and sufficient time for signal capture and analysis. Remote exploitation is not possible.