I have one of the old blue U2F tokens (~20 EUR), and pretty much only used it for GMail so far. That alone is worth it to me because many other passwords can be reset by someone that gains control over my email account.

I personally find the token much more convenient than a TOTP code via app on my smartphone. And the U2F/FIDO part is very interesting as it eliminates phishing as a risk.

I ordered a Yubikey 5 NFC just now to play around especially with the NFC part and see if I can do something useful on my phone with that. I'm still looking for a password manager that could use an NFC Yubikey to unlock it on a smartphone.

On Android there is this https://github.com/zeapo/Android-Password-Store

Works great

There are Password Store app for Android (by Zeapo). It can be interfaced with OpenKeychain in order to use NFC key. So I think you will be able to achieve full-featured OpenPGP encryption for your passwords using external hardware key.

> I'm still looking for a password manager that could use an NFC Yubikey to unlock it on a smartphone.

AFAIK that's what lastpass+yubikeyneo (nfc) did, and what this should also be able to do.

> And the U2F/FIDO part is very interesting as it eliminates phishing as a risk.

How does that work? Can't the challenge response be MITM?

The browser sends the domain as part of the request to the U2F key; so a MITM would need to be a true network-level MITM and not just a fake website MITM. The user would then have to ignore the cert error as well.

I'm not saying it's not impossible, but the it's not the primary attack U2F is designed to prevent.

well code which U2f token generate with the help of Google authenticator has ONLY 6 digits. 6 digits that's not extremely hard to brute force is that right ?

If you are using additional backup u2f token (2 tokens in total) hacker has chance 1:500 000 to find out correct PIN is my assumption right ?

You seem confused. I think you're describing TOTP, but this whole thread is about FIDO.

WebAuthn, U2F and similar FIDO based schemes are sending some public key signed blobs over the network. A PIN is purely a local protection, it's not sent over the wire. So a hacker can't just try guessing the PIN. First they need to steal your physical token, only then could they start guessing PINs for the stolen token.

And even then, the token would lock itself down after too many incorrect PIN attemtpts.

Github and google support u2f. If you are a gmail user you should get a u2f device to protect your email.

That said the cheaper yubi do this as well. I use my yubi 4 for securing my ssh key as well though this is a) a pain & b) likely theater.

I use an app based 2FA for that.

Maybe I’ll look into a YubiKey though. My problem is that I’m halfway in my own personal transition from USB A to USB C

App based 2FA is still more vulnerable to phishing than a U2F key, because it relies on the user to check they are entering the code into the right website.

It's also faster and easier (no pulling out your phone, getting a code, typing it in, just touch the key).

Plus, the keys have other features (GPG keys, etc...) which can be useful.

Ah, I didn’t know that u2F was even more phish-proof. Good to know!

I wish you successful personal transition, why you skipped USB B ?

Because host machines don’t have USB B connectors, you typically only see them on hubs and printers.

I just wrote a blog post about "Why FIDO2": [1]. Would love to hear if the messages resonate with you.

[1] https://medium.com/@0x0ece/why-choosing-a-fido2-security-key...

U2F keys make you basically immune to phishing.

for the 10 or so websites that use them

They tend to be the websites that matter a lot.