From owner-freebsd-security Thu Nov 16 22:37:11 2000 Delivered-To: freebsd-security@freebsd.org Received: from mailhost01.reflexnet.net (mailhost01.reflexnet.net [64.6.192.82]) by hub.freebsd.org (Postfix) with ESMTP id 818B537B479; Thu, 16 Nov 2000 22:37:09 -0800 (PST) Received: from 149.211.6.64.reflexcom.com ([64.6.211.149]) by mailhost01.reflexnet.net with Microsoft SMTPSVC(5.5.1877.197.19); Thu, 16 Nov 2000 22:35:25 -0800 Received: (from cjc@localhost) by 149.211.6.64.reflexcom.com (8.11.0/8.11.0) id eAH6aAq17791; Thu, 16 Nov 2000 22:36:11 -0800 (PST) (envelope-from cjc) Date: Thu, 16 Nov 2000 22:36:00 -0800 From: "Crist J . Clark" To: Rossen Raykov Cc: kris@FreeBSD.ORG, security@FreeBSD.ORG Subject: Re: Shell acces with not specified shell in /etc/shells (Re: problem using sysinstall) Message-ID: <20001116223600.B9740@149.211.6.64.reflexcom.com> Reply-To: cjclark@alum.mit.edu References: <003f01c04f3e$3c77e170$4c00000a@sage> <20001115125148.A21232@citusc17.usc.edu> <20001115131226.A21677@citusc17.usc.edu> <00d301c04f4d$e9802760$4c00000a@sage> <20001115135331.A22524@citusc17.usc.edu> <010701c04f51$8d2659e0$4c00000a@sage> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <010701c04f51$8d2659e0$4c00000a@sage>; from rraykov@sageian.com on Wed, Nov 15, 2000 at 05:15:24PM -0500 Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, Nov 15, 2000 at 05:15:24PM -0500, Rossen Raykov wrote: > Initially the /etc/shells file contains an empty line (between the comments > and the first shell). > I tough that this is the reason why login is granted on a person without > shell in /etc/passwd. > But I ware wrong! > I removed this line from /etc/shells and even after that I was able to gain > root command prompt after a valid password. > The shell is /bin/sh > > Don't this violate the idea of /etc/shells? No. A blank entry in /etc/passwd (/etc/master.passwd actually) is assumed to mean /bin/sh. From passwd(5), The shell field is the command interpreter the user prefers. If there is nothing in the shell field, the Bourne shell (/bin/sh) is assumed. This is more of a -questions thread. -- Crist J. Clark cjclark@alum.mit.edu To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message