Blank password works for root

[Bill Beeman]

"Bevan C. Bennett" <bevan at fulcrummicro.com> wrote in message
news:3FFE03D5.5030505 at fulcrummicro.com...
> Bill Beeman wrote:
> > I just discovered that I can log into my FC1 box as root with either the
> > root password, or by simply leaving the password blank!
> >
> > Functions this way from a command line, or in a terminal within either
> > KDE or Gnome.
>
> What exactly are you doing to 'log in'?
> Is this with 'su' from an existing command line, from the system
> console, or with a remote access program like ssh, telnet or rlogin?
>
> If possible, see if the behavior is consistant between using su after
> logging in as a non-root user, logging in on console, or connecting with
> ssh?
>
> The first place I'd look in this case is in /etc/pam.d/
> See if there are any files named *.rpmnew and if so check out the
> differences between them and the originals. Look especially to see if
> anything has pam_rootok.so listed, and where.

This is consistent, whether from console, existing command line, or ssh from
elsewhere,
and works whether logging in as root, or by su from another user.  In
essence, no
root security.

I've run chkrootkit-0.43, which comes up clean.

However, comparing /etc/pam.d/system-auth with system-auth.rpmnew, I noticed
the line

auth       sufficient     /lib/security/$ISA/pam_unix.so   likeauth nullok

in both. removing "likeauth nullok" seems to solve the problem, but leaves
the question of how it got that way.  System-auth notes that it will be
regenerated and user changes discarded when authconfig is run.  I'll play
with that a bit, but don't recall running that before. Anyone have any ideas
what may have generated this?

Bill