As part of our continuing research into vulnerable and malicious bootloaders, we have identified three new bootloader vulnerabilities which affect the vast majority of devices released over the past 10 years including x86-64 and ARM-based devices. These vulnerabilities could be used by an attacker to easily evade Secure Boot protections and compromise the integrity of the boot process; enabling the attacker to modify the operating system as it loads, install backdoors, and disable operating system security controls.
Article Link: One Bootloader to Load Them All - Eclypsium