If an attacker has physical access to the machine, they can bypass digital security controls.
Exploiting update mechanisms that lack cryptographic signature verification to flash modified, malicious BIOS images. Attacking and Defending BIOS
Set strong administrative passwords for BIOS/UEFI menus to prevent unauthorized local configuration changes. If an attacker has physical access to the
Attackers use clips to connect directly to the SPI flash chip on the motherboard to read or overwrite the BIOS binary. Attacking and Defending BIOS