BadUSB fails to type to a Hyundai Navigation Unit (car)

Hi everyone, I’m trying to send keystrokes to my Hyundai Sonata 21 Navigation Unit via the USB port. I can confirm that a regular keyboard works and types on it. But when I plug in my Flipper, nothing types at all.
I also tried changing the VID and PID to match an existing keyboard.

Here is an example code that won’t work:
ID 413C:2107 Dell USB Entry Keyboard:USB Input Device

Can you try entering text and numbers as a test and report back? Keep the file very simple with no preset id. I understand you used a keyboard but double check the following in case you accidentally turned USB mode off or accidentally placed the Flipper in the wrong USB port. You sound like you researched the topic but just in case I’ll warn some cables and ports only do power.

  • The cable you use a data cable.
  • Put Flipper into bad USB mode before you plug it in.
  • The USB port is in USB mode(There may be a button to change modes).
  • The USB port is capable of USB mode(it will be labelled USB if it supports USB)

Yes I can confirm that after testing, it still doesn’t work. I tested with the following:
This failed to send as well. USB Data cable, BadUSB was on, and the car’s USB port works instantly with anything plugged into it (like the physical keyboard I used).

Sounds like you checked all the boxes. Is this a made for the US vehicle?

Yes. Hyundai Sonata 2021.

I haven’t seen a problem with Flippers talking to devices made for the US market. If I can use a keyboard on a device then I can use a Flipper. Usually problems only occur in non English speaking countries. Even then it’s usually just a mistyped character here or there. I’m stumped in this case.

Maybe I’ll make a YT video demoing this issue…

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Post a link here if you do.


Could my issue be related to this other one with a BIOS?

What if you press run before you plug the Flipper into the car? I’ll check out that BIOS issue you point out. It might give me something to test a few payloads on. If I can reproduce the issue maybe I can help find a workaround.

You may also be able to use the Bluetooth version of BadUSB if the head unit supports BT keyboards. I think it’s called BadBT.

Hi, so it seems that BT-KB can only work if the target device is master and the Flipper is a slave. In this case, both my car and the Flipper act as slaves (Bluetooth Basics - SparkFun Learn). I can’t figure out how to connect 2 slave devices.

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A HID keyboard is a peripheral and should always be slave. I don’t think this is the explanation.

Shortly I learned there is a ‘Boot Interface Mode’ within USB keyboards. This mode is not supported by the Flippers BadUSB.

But I don’t need to go further, as I was informed, this is ‘common knowlege’: BadUSB in BIOS

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I believe you must pair the Flipper with the device it will control after you enter BadBT mode. If you paired the two beforehand try making the device forget the Flipper then try again. Bluetooth can be finicky.