> - sshd compiled with musl
So alpine as well as a bunch of other embedded Linuxes. Huge install base.
> - not using PAM
What you get if you try to have a minimal setup. Default sshd config if you install from source.
> - password logins enabled
The default. Super common.
> - at least one account with '*' as the password "hash"
Almost every Linux system.
> - at least one OTHER account with a valid password
Almost every Linux system.
So sure, there are caveats, but they cover a massive install base.
This is a super bad bug
I'll concede that embedded linux might be my blindspot here. Maybe cheap web hosting, too, but that seems much less likely to be using musl.
> The default. Super common.
This always seems bonkers to me. I think SSHD should give you ONE password free connection of setup to copy your key over and then it just shuts the door behind it.
It might actually a good idea, but I would likely avoid it since my built-in Bayesian filter would just mark it as spam.
Not sure whether the PHP vulnerability actually had been exploited, but I'm pretty sure there are literally thousands of machines out there affected by this ssh issue right now as we speak.
This isn't going to end well.
---
Addendum (which may or may not be related to the above) --
Everyone has heard of the tale of the boy who cried wolf. The main moral of the story is not to troll your fellow townsfolks so they don't distrust you. But everyone with a sane mind gets that.
The (IMHO) under-appreciated lesson is actually: don't be those villagers. Believe stories you are given, even if you might look like a fool for believing in them. Don't assume what happens is the same as what happened in the past. Look at the facts yourself. Trust and verify.
Sure there are native Alpine installs too, but that is far less common of a use case.