Setting Up Ubertooth on macOS for Bluetooth Hacking

Summary

This is a step-by-step guide on how to sniff Bluetooth Low Energy (BLE) packets between a Polar Vantage Smartwatch and a phone using the Ubertooth One. It will go into detail on the setup on a MacBook Air with MacOS using a python environment for the libraries that are used for the setup. Additionally every step of the actual sniff will be outlined. This guide is based on the seminar paper "Smartwatch Hacking Attack" that was written within the FH-course "Selected IT-Security Chapters".

Requirements

• Hardware tools: Ubertooth One: Firmware version: 2020-12-R1 (API:1.07)
• Unix-based Operating System: macOS (macOS Sequoia 15.1.1), on a MacBook Air with an Apple M1 chip.
• Virtual Environment: Python Environment: Python 3.12
• Packages: libusb, wget, cmake, pkg-config, setuptools, pyqt5, numpy
• Libraries: libbtbb, bleak
• Software Tools: Crackle

For the setup this guide was used and adjusted to the given scenario. [Ubertooth - Build Guide].

Description

Step 1 - Install homebrew

Enter these commands in the shell

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
eval "$(/opt/homebrew/bin/brew shellenv)"

Step 2 - Install Python Environment

Enter these commands in the shell

python3.12 -m venv myenv
source myenv/bin/activate

Step 3 - Install libusb, wget, cmake, pkg-config

Enter these commands in the shell

brew install libusb wget cmake pkg-config

Step 4 - Install the Bluetooth baseband library

Enter these commands in the shell

wget https://github.com/greatscottgadgets/libbtbb/archive/2020-12-R1.tar.gz -O libbtbb-2020-12-R1.tar.gz
tar -xf libbtbb-2020-12-R1.tar.gz
cd libbtbb-2020-12-R1
mkdir build
cd build
cmake ..
make

If errors occur with installing distutils switch to setuptools instead.

pip install setuptools

After installing the setuptools also change the "from distutils import setup" line in the the libbtbb-2020-12-R1/build/python/pcaptools/setup.py file to this:

from setuptools import setup

Also update the version in that same file to this:

version = '2020.12.R1'

If necessary set the pythonpath in case you have different python versions:

export PYTHONPATH=/Users/<username>/myenv/lib/python3.12/site-packages:$PYTHONPATH

Then retry:

make

sudo make install

Step 5 - Install the Ubertooth repository

For this part you can attach the Ubertooth One to the MacBook. BUT DO NOT USE WITHOUT ANTENNA! More information can be found here: [Ubertooth - Read the docs]

Enter these commands in the shell

wget https://github.com/greatscottgadgets/ubertooth/releases/download/2020-12-R1/ubertooth-2020-12-R1.tar.xz
tar -xf ubertooth-2020-12-R1.tar.xz
cd ubertooth-2020-12-R1/host
mkdir build
cd build
cmake ..
make

If libusb module not found errors occur go to ubertooth-2020-12-R1/host/CMakeLists.txt an add your libusb-path manually:

include_directories(/opt/homebrew/include)
link_directories(/opt/homebrew/lib)

Additionally again change the "from distutils import setup" line in the the ubertooth-2020-12-R1/host/build/python/specan_ui/setup.py file to this:

from setuptools import setup

Also update the version in that same file to this:

version = '2020.12.R1'

Then retry:

make

sudo make install

If you get errors regarding the environment variables showing that your library wasnt found you need to set the library path via the MacOs's dynamic linker.

export DYLD_LIBRARY_PATH="/usr/local/lib:$DYLD_LIBRARY_PATH"

or make it persistent in shell configurations:

~/.zshrc

Afterwards confirm the ubertooth library is working correctly:

ubertooth-util

Step 6 - Test Ubertooth One commands

Test these commands:

ubertooth-util -H
ubertooth-util -v
ubertooth-util -p
ubertooth-util -s

Update Ubertooth firmware in ubertooth-2020-12-R1/ubertooth-one-firmware-bin:

sudo ubertooth-dfu -d bluetooth_rxtx.dfu -r

In case the libubertooth library is not loading check if the paths are correct.

In ubertooth-2020-12-R1/host the following command leads to getting a list of sniffed Bluetooth packets with their Lower Address Parts (LAP):

ubertooth-rx

For collecting Upper Address Parts (UAP) from the captured packets add -z:

ubertooth-rx -z

Let it run for a while and look at the output. It will be summarized as Survey Results at the end of the output. There you can see the significant part of Bluetooth addresses of devices that were scanned.

Step 7 - Use BTLE to follow the connection of the Bluetooth device you found. (Replace with device Bluetooth Address)

ubertooth-btle -f B0:67:B5:CF:E5:10 -r test.pcap

Or create a pipe for viewing the captures directly in Wireshark:

mkfifo /tmp/pipe
ubertooth-btle -f B0:67:B5:CF:E5:10 -c /tmp/pipe

Find packages that involve the Polar Smartwatch

systime=1728247529 freq=2402 addr=8e89bed6 delta_t=34.320 ms rssi=-60
20 1b c9 28 84 1a 9e a0 02 01 06 03 02 ee fe 0d ff 6b 00 72 08 00 00 00 00 00 00 00 00 47 e9 1f 
Advertising / AA 8e89bed6 (valid)/ 27 bytes
    Channel Index: 37
    Type:  ADV_IND
    AdvA:  a0:9e:1a:84:28:c9 (public)
    AdvData: 02 01 06 03 02 ee fe 0d ff 6b 00 72 08 00 00 00 00 00 00 00 00
        Type 01 (Flags)
           00000110
               LE General Discoverable Mode
               BR/EDR Not Supported
        Type 02 (16-bit Service UUIDs, more available)
           feee
        Type ff (Manufacturer Specific Data)
           Company: Polar Electro OY
           Data: 72 08 00 00 00 00 00 00 00 00
    Data:  c9 28 84 1a 9e a0 02 01 06 03 02 ee fe 0d ff 6b 00 72 08 00 00 00 00 00 00 00 00
    CRC:   47 e9 1f

Step 8 - Use Crackle to crack packages

Enter these commands:

git clone https://github.com/mikeryan/crackle.git
cd crackle
make

Now try cracking your pcap.file

./crackle -i <your_file.pcap> -o <your_new_output_file.pcap>

In this case it wasnt possible to crack any packages from the smartwatch.

Step 9 - Install bleak library

pip install bleak

More information can be found in the bleak library documentation. [Bleak library] It also includes sample scripts which were used in the following setup.

Step 10 - Write python script for reading device UUID

Enter these commands in the shell

mkdir BLE-scripts
cd BLE-scripts
nano ble_scan.py

Write simple script to read device UUID using BleakScaner.discover() method:

import asyncio
from bleak import BleakScanner
async def scan():
    devices = await BleakScanner.discover()
    for d in devices:
        print(d)
asyncio.run(scan())

Run a scan:

python3 BLE-scripts/ble_scan.py

Here the device UUID of the Polar smartwatch was found:

C6C36C4A-7F8F-52B2-2BD7-C4F6690424E7: Polar Vantage M 8428C92D

Step 11 - Check GATT services

With the gathered device UUID check for the devices services:

nano BLE-scripts/ble_services.py

import asyncio
from bleak import BleakClient
device_uuid = "C6C36C4A-7F8F-52B2-2BD7-C4F6690424E7"
async def connect_to_device(device_uuid):
    async with BleakClient(device_uuid) as client:
        connected = client.is_connected
        print(f"Connected: {connected}")
        services = client.services
        if services is None:
            await client.get_services()
        for service in services:
            print(f"Service: {service}")
loop = asyncio.get_event_loop()
loop.run_until_complete(connect_to_device(device_uuid))

Run a services scan:

python3 BLE-scripts/ble_services.py

Now the service UUIDs that were found are going to be listed like this:

Service: 0000180a-0000-1000-8000-00805f9b34fb (Handle: 14): Device Information
Service: 0000feee-0000-1000-8000-00805f9b34fb (Handle: 29): Polar Electro Oy
Service: 0000180d-0000-1000-8000-00805f9b34fb (Handle: 38): Heart Rate
Service: 0000180f-0000-1000-8000-00805f9b34fb (Handle: 42): Battery Service

Step 12 - Get characteristics UUIDs

nano BLE-scripts/ble_characteristics.py

import asyncio
from bleak import BleakClient
device_uuid = "C6C36C4A-7F8F-52B2-2BD7-C4F6690424E7"
async def connect_to_device(device_uuid):
    async with BleakClient(device_uuid) as client:
        connected = client.is_connected
        print(f"Connected: {connected}")
        services = client.services
        if services is None:
            await client.get_services()
        for service in services:
            print(f"Service: {service.uuid} (Handle: {service.handle}): {service.description}")
            for characteristic in service.characteristics:
                print(f"  Characteristic: {characteristic.uuid} (Handle: {characteristic.handle}) - Properties: {cha$
loop = asyncio.get_event_loop()
loop.run_until_complete(connect_to_device(device_uuid))

Now run the script:

python3 BLE-scripts/ble_characteristics.py

Expected output:

Service: 0000180a-0000-1000-8000-00805f9b34fb (Handle: 14): Device Information
 Characteristic: 00002a29-0000-1000-8000-00805f9b34fb (Handle: 15) - Properties: ['read']
 Characteristic: 00002a24-0000-1000-8000-00805f9b34fb (Handle: 17) - Properties: ['read']
 Characteristic: 00002a25-0000-1000-8000-00805f9b34fb (Handle: 19) - Properties: ['read']
 Characteristic: 00002a27-0000-1000-8000-00805f9b34fb (Handle: 21) - Properties: ['read']
 Characteristic: 00002a26-0000-1000-8000-00805f9b34fb (Handle: 23) - Properties: ['read']
 Characteristic: 00002a28-0000-1000-8000-00805f9b34fb (Handle: 25) - Properties: ['read']
 Characteristic: 00002a23-0000-1000-8000-00805f9b34fb (Handle: 27) - Properties: ['read']
Service: 0000feee-0000-1000-8000-00805f9b34fb (Handle: 29): Polar Electro Oy
 Characteristic: fb005c51-02e7-f387-1cad-8acd2d8df0c8 (Handle: 30) - Properties: ['write-without-response', 'write', 'notify']
 Characteristic: fb005c52-02e7-f387-1cad-8acd2d8df0c8 (Handle: 33) - Properties: ['notify']
 Characteristic: fb005c53-02e7-f387-1cad-8acd2d8df0c8 (Handle: 36) - Properties: ['write-without-response', 'write']
Service: 0000180d-0000-1000-8000-00805f9b34fb (Handle: 38): Heart Rate
 Characteristic: 00002a37-0000-1000-8000-00805f9b34fb (Handle: 39) - Properties: ['notify']
Service: 0000180f-0000-1000-8000-00805f9b34fb (Handle: 42): Battery Service
 Characteristic: 00002a19-0000-1000-8000-00805f9b34fb (Handle: 43) - Properties: ['read', 'notify']

Step 13 - Read data

Now add a script for reading the actual data. Make sure to use the characteristics UUIDs you have found out.

nano BLE-scripts/ble_read.py

import asyncio
from bleak import BleakClient
device_uuid = "C6C36C4A-7F8F-52B2-2BD7-C4F6690424E7"
HEART_RATE_CHAR_UUID = "00002a37-0000-1000-8000-00805f9b34fb"
BATTERY_LEVEL_CHAR_UUID = "00002a19-0000-1000-8000-00805f9b34fb"
async def connect_and_read_data(device_uuid):
    async with BleakClient(device_uuid) as client:
        connected = client.is_connected
        print(f"Connected: {connected}")
        if connected:
            try:
                heart_rate = await client.read_gatt_char(HEART_RATE_CHAR_UUID)
                heart_rate = int(heart_rate_data[1])
                print(f"Heart Rate: {heart_rate} bpm")
            except Exception as e:
                print(f"Failed to read heart rate: {e}")
            try:
                battery_level = await client.read_gatt_char(BATTERY_LEVEL_CHAR_UUID)
                print(f"Battery Level: {int(battery_level[0])}%")
            except Exception as e:
                print(f"Failed to read battery level: {e}")
loop = asyncio.get_event_loop()
loop.run_until_complete(connect_and_read_data(device_uuid))

Run script:

python3 BLE-scripts/ble_read.py

In the output the battery level was succesfully read and printed out. The heart rate couldn't be accessed because it only has the notify property and no option for reading:

Connected: True
Failed to read heart rate: Failed to read characteristic 39: Error Domain=CBATTErrorDomain Code=2 "Reading is not permitted." UserInfo={NSLocalizedDescription=Reading is not permitted.}
Battery Level: 16%

Step 14 - Subscribe to heart rate notifications

nano BLE-scripts/ble_subscribe.py

import asyncio
from bleak import BleakClient
device_uuid = "C6C36C4A-7F8F-52B2-2BD7-C4F6690424E7"
HEART_RATE_CHAR_UUID = "00002a37-0000-1000-8000-00805f9b34fb"
def heart_rate_handler(sender, data):
    heart_rate = int(data[1]) if len(data) > 1 else None
    print(f"Heart Rate from {sender}: {heart_rate} bpm")
async def connect_and_subscribe(device_uuid):
    async with BleakClient(device_uuid) as client:
        connected = client.is_connected
        print(f"Connected: {connected}")
        if connected:
            try:
                await client.start_notify(HEART_RATE_CHAR_UUID, heart_rate_handler)
                print("Subscribed to heart rate notifications.")
                await asyncio.sleep(60)
                await client.stop_notify(HEART_RATE_CHAR_UUID)
                print("Stopped heart rate notifications.")
            except Exception as e:
                print(f"Failed to subscribe to heart rate notifications: {e}")
asyncio.run(connect_and_subscribe(device_uuid))

python3 BLE-scripts/ble_subscribe.py

It was not possible to get the heart rate data even though the notify property was assigned. That is because typically battery status data is on a lower securiy level than heart rate data. More information on GATT can be found here: https://www.bluetooth.com/de/bluetooth-resources/intro-to-bluetooth-gap-gatt/

This is the output of the failed try:

Connected: True
Subscribed to heart rate notifications.
Stopped heart rate notifications.

Used Hardware

• Ubertooth One, 2.4 GHz wireless development platform

• Polar Vantage M

• Apple iPhone 13 mini

• MacBook Air M1, 2020

• Samsung Galaxy J3

Courses

• Selected IT-Security Chapters (2024)

Author

Are Maksimović

References

• https://ubertooth.readthedocs.io/en/latest/
• https://www.greatscottgadgets.com/ubertoothone/
• https://codemuch.net/posts/bluetooth-hacking/
• https://bleak.readthedocs.io/en/latest/usage.html
• https://www.bluetooth.com/de/bluetooth-resources/intro-to-bluetooth-gap-gatt/
• https://support.polar.com/en/vantage-m#all
• https://wiki.elvis.science/index.php?title=B-LE_-_GATT_Architectural_Overview