[Android wallet app] Updating fingerprint data does not force pin reauth

[danielbanfield]

Device: Pixel 5
Android version: 12

As in subject. Steps to reproduce:

1. Unlock wallet app using fingerprint
2. Close app
3. Go to android settings
4. Add a fingerprint using the device pin
5. Open wallet app
6. Unlock using the new fingerprint

Other apps such as my banking apps have forced a reauth of the app password or pin with a specific message saying that the fingerprint data has changed therefore a reauth is necessary. So the android API does allow checking this. The loopring wallet should do the same.

An angle of attack can be to brute force a device pin (not difficult from what I've read online, under 17hrs for a 4 digit pin https://github.com/urbanadventurer/Android-PIN-Bruteforce) add a fingerprint and then gain access to the wallet. I presume the loopring wallet pin security is better than Android (which is pretty useless: 30 second wait every 5 tries which leaves it open to brute force attacks like above).

Sadly it seems the Metamask wallet app also fails to ask for a password reauth, but that's not your problem ;)

Thanks