Web Authentication in Firefox for Android

Firefox for Android (Fennec) now supports the Web Authentication API as of version 68. WebAuthn blends public-key cryptography into web application logins, and is our best technical response to credential phishing. Applications leveraging WebAuthn gain new  second factor and “passwordless” biometric authentication capabilities. Now, Firefox for Android matches our support for Passwordless Logins using Windows Hello. As a result, even while mobile you can still obtain the highest level of anti-phishing account security.

Firefox for Android uses your device’s native capabilities: On certain devices, you can use built-in biometrics scanners for authentication. You can also use security keys that support Bluetooth, NFC, or can be plugged into the phone’s USB port.

The attached video shows the usage of Web Authentication with a built-in fingerprint scanner: The demo website enrolls a new security key in the account using the fingerprint, and then subsequently logs in using that fingerprint (and without requiring a password).

Adoption of Web Authentication by major websites is underway: Google, Microsoft, and Dropbox all support WebAuthn via their respective Account Security Settings’ “2-Step Verification” menu.

A few notes

For technical reasons, Firefox for Android does not support the older, backwards-compatible FIDO U2F Javascript API, which we enabled on Desktop earlier in 2019. For details as to why, see bug 1550625.

Currently Firefox Preview for Android does not support Web Authentication. As Preview matures, Web Authentication will be joining its feature set.