Sounds to be like we're replacing the username and the password, i.e. something you know with username and your phone, i.e. something you have.
It sounds like it's still a one factor authentication system, but different.
It sounds like it's still a one factor authentication system, but different.
The standard allows for service to demand that the authentication device performs an additional factor authentication. Which is usually either a PIN or biometrics, and your device attests to doing this during authentication.
So then you have two complete factors “something you have” (your phone) and “something you are” (biometrics) or “something you know” (unlock PIN for device).
If you were sending an actual copy of your biometric data to the remote authentication service, then maybe you could make that argument.
But that never happens, no FIDO biometric device sends a biometric fingerprint that could be reproduced by a different device. The device authenticates you with biometrics, then uses that data to unlock a private key, which is then used to answer a challenge-response request from the authenticating service.
If you don’t the device, then it’s pretty much impossible for you to correctly answer that challenge-response, despite being in possession of the biometric features that device would use to authenticate you.
So you can’t use your biometrics as a username. Because the device measuring the biometric data pushes that data through a mono-directional, randomly generated (at device manufacture), hash function, that exists within that device only. Take your biometrics else where (I.e same device type/model but different physical object), and you’ll get a different output even with identical inputs. Which would be a pretty useless username.
> I'm not sure something you are counts as a security factor.
You should take that up with NIST then: https://www.nist.gov/itl/smallbusinesscyber/guidance-topic/m...
In the same way that the security of something you know is a scale based on “how difficult is your password to guess” or “how hard is it to crack the hash” the security of something you are is a scale based on “how difficult is it for someone to create a fake that tricks this specific machine into thinking it’s reading metrics from a live human.”
The security lives in the system reading the metrics not your body which is why you don’t have to rotate your face every 90 days.
A cheap fingerprint reader is the 4 digit pin of something you are. Retina scans that take temperature, look for blood flow and eye movement are the correct horse battery staple.
- so what happens if you don't have your phone at time of login?
- if I enroll on iPhone, is my identity forever tied to Apple or can it be migrated to Android if I ever wanted to change platforms?
- Can Apple/Google/Microsoft ever block/ban my account, preventing me from logging into my bank, etc that use FIDO login?
You technically should be able to migrate from one provider to another, it remains to be seen how easy Apple and Google will make the process.
That last one is a great question that I don't know the answer to.
On a UX level, the transfer to another syncing security key "provider" is going to be interesting, if they even do that at all - I kind of doubt they'll have a "transfer your iCloud passkeys to your Chrome password manager" and they'll instead say "go to each service and enroll a new security key via your new syncing key manager". On a technical level, I wholly imagine there'll be a tool that pulls iCloud Passkeys[0] via the MacOS Keychain application and then inserts them into your new key manager.
0: https://developer.apple.com/documentation/authenticationserv...
Depends on if they allow you to turn off password+2FA login entirely, which I only see being possible with something like Advanced Protection Program[0] which can already be used to enforce "Only allow authentication with my password+security keys; there is no way for Google Support to remove 2fa; if I lose the keys, the account's lost".
> - if I enroll on iPhone, is my identity forever tied to Apple or can it be migrated to Android if I ever wanted to change platforms?
I imagine they'll say "login to each website" (which you can do via iOS if you use qr android login[1]) then "re-enroll with your new provider", but I hope there will be an actual export/import or migration experience.
> - Can Apple/Google/Microsoft ever block/ban my account, preventing me from logging into my bank, etc that use FIDO login?
Assuming they don't change how Chrome and iCloud keychain currently works, everything synced should stay on your already signed-in devices, so hopefully you can continue to use your devices as authenticators until you can log into each service and register a regular, hardware key for sign-in.
0: https://landing.google.com/advancedprotection/
1: https://www.chromestory.com/2021/12/qr-code-2fa/#:~:text=Her... I personally tried this with my iPhone, and my phone prompted me to use an iCloud Passkey. I was able to confirm that, by enrolling my iPhone as a security key on GitHub, then this 'BLE Webauthn' feature allowed me to sign in to GitHub on my desktop Chrome browser via my phone. Only downside to this is that the desktop must have a bluetooth card, but hopefully motherboards will continue to come integrated with wifi+bluetooth.
A good FIDO implementation will give you the ability to enroll multiple authenticators. In fact, if you can't, you're basically going against the WebAuthn spec.
"Relying Parties SHOULD allow and encourage users to register multiple credentials to the same account. Relying Parties SHOULD make use of the excludeCredentials and user.id options to ensure that these different credentials are bound to different authenticators."
Basically, you should enroll your iPhone and a backup key. And if you get an Android device, you log in with the Android device using a backup key, and enroll the Android device and remove the iPhone. Alternatively, you remove the iPhone authentication using the iPhone, and enroll the Android device using an alternative authentication method (like traditional username/password).
You can’t login. Same as it is with any 2FA system where you don’t have access to the second factor.
> - if I enroll on iPhone, is my identity forever tied to Apple or can it be migrated to Android if I ever wanted to change platforms?
At a minimum services should support multiple authentication devices/tokens. So you can enrol both an iOS device and Android device, or any other FIDO device E.g. YubiKey.
This is already the standard approach for FIDO tokens, and basically a requirement for existing services, because we don’t currently have FIDO token syncing.
I would hope that these syncing services will also allow you to export your private key. But that’s a slightly scary prospect because it would allow the holder of that key to authenticate as you anywhere.
> - Can Apple/Google/Microsoft ever block/ban my account, preventing me from logging into my bank, etc that use FIDO login?
Services will still need a credential recovery process. People lose phone etc everyday. I imagine your bank will happy reset your credentials if you turned up in-person holding government identification.
If you don't accept their 10,000 word ever-changing terms of use, and if don't let them check for the marks on your forehead or right hand, then yes, you won't be able to buy or sell.
You don't need an Apple/Google/Microsoft account to use WebAuthn on another website, it's based on the biometrics on your local device. Syncing that credential across your devices with the same account is just an optional extra feature.
Its not like InfoSec cares if the business functions, that's not their job.