On Mon, 23 Nov 2020 03:32:08 +0100 Taylan Kammer wrote: > On 23.11.2020 00:20, Christopher Lemmer Webber wrote: > > Okay, I just realized I left a friend vulnerable by guiding them > > through a Guix graphical install and telling them it would give > > them a decent setup. They turned on openssh support. > > > > Then I realized their config had password-authentication? on. > > > > That's unacceptable. We need to change this default. This is > > known to leave users open to attack, and selecting a password > > secure enough against brute forcing is fairly difficult, much more > > difficult than only allowing entry by keys. Plus, few > > distributions do what we're doing anymore, precisely because of > > wanting to be secure by default. > > > > Yes, I know some people want password authentication on as part of a > > bootstrapping process. Fine... those users know to put it on. > > Let's not leave our users open to attack by default though. > > > > Happy to produce a patch and change the documentation, but I'd like > > to hear that we have consensus to make this change. But we should, > > because otherwise else I think we're going to hurt users. > > I think most ideal would be if the user is asked the following two > questions, with a short explanation of what each means: > > - Allow root login via SSH? > > - Allow password authentication in SSH? > > (I think Debian does this.) > > Because as you say, on one hand password authentication in SSH can be > a security risk. But on the other hand many machines never have > their SSH port exposed to the Internet, and the intranet is assumed > to be safe. In those cases it would be an annoyance to have to enable > it manually. > > Both points apply to direct root login as well I think. > > Allowing password authentication but disabling root login might also > be considered safe enough on machines exposed to the Internet, > because the attacker needs to guess the username as well. Only > presents a small increase in complexity for the attacker though. > > > - Taylan > > > Most people won't know why allowing password authentication is unsecure. Either it should be worded differently, have a warning, or not be an option. Same goes doubly so for allowing root login.