Part 4/11:
For instance, one common target is the device's firmware signature verification process, which ensures only authentic code runs on the hardware. This process typically involves calculating a cryptographic signature of the firmware and verifying it against a trusted value. Attackers can attempt to "fool" this process by inducing faults—using lasers, electromagnetic interference, or even physical contact—to cause the CPU to skip critical verification steps.
In theoretical terms, this could be represented as causing the CPU to ignore a condition that rejects unauthorized code, effectively allowing unverified firmware to execute. While the actual implementation of such techniques is complex and requires specialized equipment, their viability remains a significant concern for hardware security.