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Remote Triggers for the Bash Bunny Mark II
One of the greatest new features of the Bash Bunny Mark II is remote triggers. With this, a payload — or multiple stages of a payload — can be triggered from afar. These can be done with any bluetooth low-energy device, including most smartphones. In this article I'll demonstrate how to use this handy new feature.

Imagine a social engineering engagement where the target is asked to print a document from a flash drive. The Bash Bunny, with ATTACKMODE STORAGE, will present itself as just such a benign device in the first stage of an attack. Then the opportunity presents itself to launch a second stage — emulating a HID device and performing keystroke injection — when the target turns their back to fetch the printout.

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# Remote Trigger for Bash Bunny Mark II Example
#
LED SETUP
#
# Stage 1: Benign flash drive
#
ATTACKMODE STORAGE
LED STAGE1
WAIT_FOR_PRESENT myphone
#
# Stage 2: Evil keystroke injection attack
#
ATTACKMODE STORAGE HID
LED STAGE2
QUACK GUI r
QUACK DELAY 200
QUACK STRING cmd /k tree c:\
QUACK ENTER

For this attack to proceed to the second stage, you simply need to advertise the BLE device named "myphone". This can either be the name of a BLE device that advertises whenever it's on — like a bluetooth speaker — or advertisements specifically sent from an app like BLE Tool.

Any bluetooth utility capable of broadcasting BLE advertisements will work. In testing I often times find myself using the highly configurable and aptly named BLE Tool for Android. If you choose to test with it, there are only 3 steps to follow:
  1. 1.
    Tap GATT Server
  2. 2.
    Specify a device name from the Advertiser settings (under the [...] menu)
  3. 3.
    Tap Start Advertising

The WAIT_FOR_PRESENT and WAIT_FOR_NOT_PRESENT extensions work by setting the BLE module to Observation mode (AT+ROLE=2), then continuously saving the scanned airwaves to a temporary file on a 5 second interval (timeout 5s cat /dev/ttyS1 > /tmp/bt_observation). That binary file is then checked for the string value specified with the extension (grep -qao $1 /tmp/bt_observation).
If you're curious what other advertisements might be found, consider running strings against this file while in observation mode. For faster remote triggers, consider modifying the extension for shorter scan durations.
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On this page
THE SCENARIO
THE CODE
PULLING OFF THE ATTACK
CONFIGURING BLE TOOL
HOW REMOTE TRIGGERS WORK