Path: utzoo!attcan!uunet!wuarchive!brutus.cs.uiuc.edu!apple!ames!mailrus!purdue!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.unix.questions
Subject: Re: Password entry
Message-ID: <10813@smoke.BRL.MIL>
Date: 24 Aug 89 18:43:33 GMT
References: <10975@boulder.Colorado.EDU>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 11

In article <10975@boulder.Colorado.EDU> bobk@fred.colorado.edu (Bob Kinne) writes:
>What is the purpose of the following /etc/passwd entry?
>::0:0:::	(null login, password, and shell)

To permit anyone at all to become super-user without having to supply a
password!

These entries are created as a side-effect of a deficiency in the pwd-
reading library routines in Berkeley variants of UNIX, when the password
file is updated and there is some malformed entry in it.  You really
ought to fix the library routine and then rebuild /bin/passwd etc.