uefi secureboot variable interceptor

research project demonstrating runtime interception of uefi variable access during the boot process

this project implements a runtime hook for efi_runtime_services->getvariable, allowing controlled responses when firmware variables are queried by the bootloader.

the application installs the hook and then transparently transfers execution to the original windows boot manager.

features

• intercepts uefi runtime variable access
• custom handler for secureboot variable
• preserves original firmware behavior for all other variables
• transparent boot chain continuation
• minimal footprint during the boot process

one important variable is: guid: efi_global_variable this variable is used by the windows boot manager to determine whether secure boot is enabled.

the project implements a fake secure boot response by intercepting the request and returning a controlled value instead of the firmware-provided one.

fake secure boot flow

uefi firmware -> runtime services -> efi_runtime_services->getvariable -> custom hook (wsgetvariable) -> fake secureboot value -> windows boot manager -> normal boot process

this project is provided for educational and research purposes only.