Question Can I use my cell phone as a "Yubikey" for my notebook?

[Desertprep]

If I understand correctly, a "yubikey" is a kind of thumbdrive that acts as a digital lock for a computer - without the yubikey plugged in, no go. Is it possible for me to put an app on my phone, connect the phone to the notebook and use the cell phone as my yubikey? My cell phone is FAR less likely to disappear, while a small usb shaped object....that will be a bigger challenge.....and...just thought of something...if this is possible, is it possible to use a blutooth or wifi connection instead of a physical cable?

 

[Cilantro7536]

You can try this, but success will depend on your computer (Windows 11 works; unclear on 10), your phone (if Android, 13+), etc.

1. Try it on a website, either this demo site (https://www.token2.com/tools/fido2-demo) or a Discourse forum (one that enables security key 2FA).
2. Turn on Bluetooth on both the computer and the phone.
3. "Register" on the above site, or add "Physical Security Keys" on a Discourse forum.
4. Pick "iPhone, iPad, or Android" when prompted by Windows.
5. Scan the QR code using your phone’s default scanner.

On my Android 13 phone, I had to install Chrome (with its Google password manager which I didn’t have) to get this to work.

AFAIK, FIDO2 doesn’t work over Wi-Fi (due to the “being present” requirement) and will most likely only work with Bluetooth (and perhaps NFC).

I think people attach their physical security key to their keyring to reduce the chance of losing it.