FIDO2 HID Bridge
June 29, 2026 ยท View on GitHub
This repository contains sources for a Linux virtual USB-HID FIDO2 device.
This device will receive FIDO2 CTAP2.1 commands, and forward them to an attached PC/SC authenticator.
This allows using authenticators over PC/SC from applications that only support USB-HID, such as Firefox; with this program running you can use NFC authenticators or Smartcards.
Setup
You'll need to install dependencies:
poetry install
And then build the redistributable:
poetry run package
This will produce a dist/fido2-hid-bridge that you can run. You might need to be root
or otherwise get access to raw HID devices (permissions on /dev/uhid):
sudo -E ./dist/fido2-hid-bridge
Implementation Details
This uses the Linux kernel UHID device facility, and the python-fido2 library.
It relays USB-HID packets to PC/SC.
Nothing more to it than that.