RFC 8252 is a complete joke

[Michael Thomas <mike@xxxxxxxx>]

About 10 years ago I discovered that IETF was working on OAUTH as a 
replacement for sites to need user credentials to do things on their 
users' behalf, typically for use to post stuff to social media sites at 
the time, but also as a convenient general login mechanism. I had a 
native app I wrote and I didn't like having to store use credentials so 
that seemed great. However when I thought about it it seemed there was 
nothing to prevent me to still get the login credentials from the user 
of my app. Native apps, like phone apps, have complete control of the UI 
unlike a web browser which can be assumed to be a neutral player from 
the user's standpoint. When an app asks you for your login credentials 
for, say, Facebook you have to make a decision whether you trust the app 
or not. With OAUTH it makes it seem like it's safe regardless whether 
you trust the app or not.

It isn't. Since the app has complete control of the UI unlike a browser, 
it completely controls what the user sees. There is an infinite number 
of ways for a native app to game the user to get their credentials while 
still completing the OAUTH transaction on the user's behalf. I brought 
this up to the OAUTH wg at the time and was roundly flamed by the 
working group and especially the lead author at the time (who it seems 
flamed out later for seemingly unrelated reasons). The end result was a 
little line or two blurb in the security considerations and the end 
result is, as I predicted, that nobody would care about OAUTH use in 
native apps and it would become commonplace.

Later I heard that the OAUTH wg had created RFC 8252 which at first I 
thought was vindication after the hostility I was shown by the wg. I was 
looking it up again today though and found out that instead of just 
being an information "don't do this" it is in fact a BCP. The jist is 
that native apps should use browsers to do the login. This is tantamount 
to asking foxes to be nice while guarding the hen house. Or closer to 
home, that RFC 3514 and the evil bit should be employed. Native apps 
intent on stealing your credentials can still steal your credentials no 
matter what RFC 8252 says and the user will be none the wiser.

What should be the BCP is that OAUTH should *never* be used for native 
apps and that users should *always* be cognizant that an evil app can 
steal their credentials just like when I specifically had to store them 
for my app to do stuff on their behalf. How on earth did the IESG let 
this get through? I mean seriously, this is a complete joke. Asking 
people to not be evil is not security and is certainly not a best common 
practice. This RFC should either be declared historic or rewritten.

Mike