I created a tool today for embedded device security assessments. Basically what it does it searches the linux `mtd` partitions to find the U-Boot environment variable location and then gives the correct format for the `fw_env.config` file that the U-Boot utilities `fw_setenv` and `fw_printenv` use. So, if those utilities are not installed with the proper config file on the embedded device, you can statically compile them and create the proper config file to use them to modify the U-Boot environment variables from the Linux host.
Show HN: U-Boot Fw_env.config Bruteforcer | Heykuki News