bug#43302: password shows up in shell buffer (27.1)

[Eli Zaretskii]

> From: Nicholas Drozd <nicholasdrozd@gmail.com>
> Date: Fri, 12 Feb 2021 14:50:01 -0600
> Cc: 43302@debbugs.gnu.org
> 
> Your workaround works, but the fact remains that the behavior changed
> between 26 and 27, and it changed in a way that I as a user found
> disturbing. I switched to 27, and on my first session I ran a script
> that queried for a password. Previously Emacs had hid the password as
> I expected, but in 27 my password was unexpectedly exposed on the
> screen. It's a bug, and it should be fixed. (I would try to fix it
> myself, but I have no idea where to start. With a little guidance I
> could take a crack at it.)

I'd start at comint-watch-for-password-prompt.