Now we will walk through building Coreboot from scratch. We will first install the required tools, then download Coreboot’s source code, build its toolchain, configure it for your mainboard, and finally compile it into a ROM file you can flash.
Why Coreboot?
Before we can flash Coreboot internally on a ThinkPad, we need to make sure the BIOS version is vulnerable enough to be overwritten.
External flashing is sometimes necessary instead of internal flashing. The main reasons are:
Flashing firmware always carries some risk.
Coreboot supports several Lenovo ThinkPad models. In this guide, we’ll focus on models where Coreboot can be installed via internal flashing, meaning you don’t need to open up the laptop or use external flashing tools. This makes the process much easier compared to installing Coreboot, which usually requires disassembly and external flashing.
Before flashing Coreboot internally, it’s important to understand the security protections built into the BIOS and how older versions can be exploited to bypass them.