bluescan ---- A powerful Bluetooth scanner

This document is also available in Chinese（中文）.

This project is maintained by Sourcell Xu from DBAPP Security HatLab. Under the terms stated in the GPL-3.0, anyone may redistribute copies of it to anyone.

Bluetooth is a complex protocol, and a good scanner can quickly help us peek inside its secrets. But previous Bluetooth scanners suffered from a number of problems such as incomplete functionality, unintuitive information and out of repair. So we came up with this powerful Bluetooth scanner based on modern Python 3 ---- bluescan.

When hacking Bluetooth targets, bluescan can be very useful for intelligence collecting. It can collect the following information:

• BR devices
• LE devices
• BR LMP features
• LE LL features
• SMP Pairing features
• Real-time advertising physical channel PDU
• SDP services
• GATT services
• Vulnerabilities (demo)

Requirements

bluescan is based on BlueZ, the official Linux Bluetooth stack. It only supports running on Linux, and the following packages need to be installed:

sudo apt install libglib2.0-dev libbluetooth-dev

Python 3 is also necessary for running bluescan. Currently bluescan can support python 3.9.1.

When you play this tool in a Linux virtual machine, making a USB Bluetooth adapter exclusive to it is recommended, like the Ostran Bluetooth USB Adapter OST-105 CSR 8150 v4.0 for 99 RMB：

Parani UD100-G03 is better than the above-mentioned Ostran adapter. But of course it will be a little more expensive, 560 RMB：

And if you want to try the vulnerability scanning, see README.md of ojasookert/CVE-2017-0785 to resolve dependencies.

Dedicated firmware for micro:bit

If you want to use bluescan to sniff the advertising physical channel PDU (-m le --adv), you need to execute the following command to download the dedicated firmware bin/bluescan-advsniff-combined.hex to 1 or 3 micro:bit(s). It is recommended to use 3 micro:bits at the same time.

cd bluescan
cp bin/bluescan-advsniff-combined.hex /media/${USER}/MICROBIT
cp bin/bluescan-advsniff-combined.hex /media/${USER}/MICROBIT1
cp bin/bluescan-advsniff-combined.hex /media/${USER}/MICROBIT2

If you want to compile the firmware yourself, first install the following packages:

sudo apt install yotta ninja-build

Then execute the following command, it will automatically compile (requires network to automatically resolve dependencies) and download the firmware to the micro:bit(s) which connected to your PC:

cd bluescan
make flash

Install

The lastest bluescan will be uploaded to PyPI, so the following command can install bluescan:

sudo pip3 install bluescan

Usage

$ bluescan -h
bluescan v0.5.0

A powerful Bluetooth scanner.

Author: Sourcell Xu from DBAPP Security HatLab.

License: GPL-3.0

Usage:
    bluescan (-h | --help)
    bluescan (-v | --version)
    bluescan [-i <hci>] -m br [--inquiry-len=<n>]
    bluescan [-i <hci>] -m br --lmp-feature BD_ADDR
    bluescan [-i <hci>] -m le [--scan-type=<type>] [--timeout=<sec>] [--sort=<key>]
    bluescan [-i <hci>] -m le [--ll-feature|--smp-feature] [--timeout=<sec>] --addr-type=<type> BD_ADDR
    bluescan -m le --adv [--channel=<num>]
    bluescan [-i <hci>] -m sdp BD_ADDR
    bluescan [-i <hci>] -m gatt [--include-descriptor] --addr-type=<type> BD_ADDR
    bluescan [-i <hci>] -m vuln [--addr-type=<type>] BD_ADDR

Arguments:
    BD_ADDR    Target Bluetooth device address. FF:FF:FF:00:00:00 means local 
               device.

Options:
    -h, --help              Display this help.
    -v, --version           Show the version.
    -i <hci>                HCI device used for subsequent scans. [default: The first HCI device]
    -m <mode>               Scan mode, support BR, LE, SDP, GATT and vuln.
    --inquiry-len=<n>       Inquiry_Length parameter of HCI_Inquiry command. [default: 8]
    --lmp-feature           Scan LMP features of the remote BR/EDR device.
    --scan-type=<type>      Scan type used for scanning LE devices, active or 
                            passive. [default: active]
    --timeout=<sec>         Duration of the LE scanning, but may not be precise. [default: 10]
    --sort=<key>            Sort the discovered devices by key, only support 
                            RSSI now. [default: rssi]
    --adv                   Sniff advertising physical channel PDU. Need at 
                            least one micro:bit.
    --ll-feature            Scan LL features of the remote LE device.
    --smp-feature           Detect pairing features of the remote LE device.
    --channel=<num>         LE advertising physical channel, 37, 38 or 39). [default: 37,38,39]
    --include-descriptor    Fetch descriptor information.
    --addr-type=<type>      Type of the LE address, public or random.

Scan BR devices -m br

Classic Bluetooth devices may use three technologies: BR (Basic Rate), EDR (Enhanced Data Rate), and AMP (Alternate MAC/PHY). Since they all belong to the Basic Rate system, so when scanning these devices we call them BR device scanning:

As shown above, through BR device scanning, we can get the address, page scan repetition mode, class of device, clock offset, RSSI, and the extended inquiry response (Name, TX power, and so on) of the surrounding classic Bluetooth devices.

Scan LE devices -m le

Bluetooth technology, in addition to the Basic Rate system, is Low Energy (LE) system. When scanning Bluetooth low energy devices, it is called LE device scanning:

As shown above, through LE device scanning, we can get the address, address type, connection status, RSSI, and GAP data of the surrounding LE devices.

Scan BR LMP features -m br --lmp-feature

Detecting the LMP features of classic Bluetooth devices allows us to judge the underlying security features of them:

Scan LE LL features -m le --ll-feature

Detecting the LL (Link Layer) features fo the LE devices:

Detect SMP Pairing features -m le --smp-feature

Detecting the SMP Pairing features of the remote LE device:

Sniffing advertising physical channel PDU -m le --adv

Compared with scanning adove the HCI, using micro:bit to sniff the advertising physical channel PDU at the link layer, you can get richer LE device activity information:

💡 The scan mode has a hidden function.

Scan SDP services -m sdp

Classic Bluetooth devices tell the outside world about their open services through SDP. After SDP scanning, we can get service records of them:

You can try to connect to these services for further hacking.

Scan GATT services -m gatt

LE devices tell the outside world about their open services through GATT. After GATT scanning, we can get the GATT service of them. You can try to read and write these GATT data for further hacking:

Vulnerabilities scanning -m vuln (demo)

Vulnerability scanning is still in the demo stage, and currently only supports CVE-2017-0785:

$ sudo bluescan -m vuln --addr-type=br ??:??:??:??:??:??
... ...
CVE-2017-0785

FAQ

• Exception: "Can't find the ID of hci0 in rfkill"

  Some old versions of rfkill do not support -r and -n options, like:

  # Ubuntu 16.04.1
  rfkill --version
  # rfkill 0.5-1ubuntu3 (Ubuntu)"
  

  Please upgrade rfkill or OS to solve this problem.

  PS: My system is Kali, and the version of rfkill is:

  # Kali
  rfkill --version
  # rfkill from util-linux 2.36.1
  

If you encounter the following error, restart bluetooth service to recover (sudo systemctl restart bluetooth.service):

• [ERROR] Failed to execute management command 'scanend' (code: 11, error: Rejected)