fuzzboot

Simple fuzzer for discovering hidden fastboot gems.

Forked from abootool By Roee Hay / Aleph Research, HCL Technologies

Modus Operandi: Based on static knowledge (strings fetched from available bootloader images), dynamically fuzz for hidden fastboot OEM commands.

Appears in the USENIX WOOT '17 paper: fastboot oem vuln: Android Bootloader Vulnerabilities in Vendor Customizations (USENIX WOOT '17)

Usage

Download your favourite OTAs/Factory images and populate with fuzzboot.py -a <dir>. fuzzboot.py -l will then show you the populated images.
Hook your device to the nearest USB port and run fuzzboot.py. It will try to automatically discover the product or OEM. If it fails, it will fuzz the device with all of the available strings. One can force a specific OEM using -e <oem> parameter. When it finishes, the tool prints the discovered positive commands (including ones whose response is a fastboot failure), discovered restricted commands, commands which timed-out, and commands which have triggered various errors.

See fuzzboot.cfg and fuzzboot.py -h for advanced usage.

Explanation of progress bar:

[####......] [012923/030245/+01/R02/T01/E02] [CMD: foobar] [LAST: fdsaf]
  |             |      |    |   |    |   |        |         |
  |             |      |    |   |    |   |        |         `-> Last non-neg CMD
  |             |      |    |   |    |   |        `-----------> Last CMD
  |             |      |    |   |    |   `--------------------> # of CMDs that caused USB errors
  |             |      |    |   |    `------------------------> # of CMDs that caused timeouts
  |             |      |    |   `-----------------------------> # of restricted CMDs
  |             |      |    `---------------------------------> # of positive CMDs
  |             |      `--------------------------------------> Total # of CMDs
  |             `---------------------------------------------> # of tested CMDS
  `-----------------------------------------------------------> % completed

Dependencies

python-adb
android-sdk-tools
Boot.img tools (only required for populating fugu images)

Tips

ADB-authorize your device for automatic-recovery from fastboot reboots.
If you had populated many images, running with -g would improve loading times.
If the device hangs, do not reset fuzzboot, but rather reboot the device (into fastboot). fuzzboot will then proceed automatically.

Tested on

Host environment:

Ubuntu 17.04 zesty
macOS Mojave 10.14.5

Example

Add device from image file: