From owner-freebsd-security Mon Jan 20 16:24:46 2003 Delivered-To: freebsd-security@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 90F1137B401 for ; Mon, 20 Jan 2003 16:24:41 -0800 (PST) Received: from sccrmhc01.attbi.com (sccrmhc01.attbi.com [204.127.202.61]) by mx1.FreeBSD.org (Postfix) with ESMTP id 872BA43ED8 for ; Mon, 20 Jan 2003 16:24:40 -0800 (PST) (envelope-from crist.clark@attbi.com) Received: from blossom.cjclark.org (12-234-89-252.client.attbi.com[12.234.89.252]) by sccrmhc01.attbi.com (sccrmhc01) with ESMTP id <2003012100243400100hncl6e>; Tue, 21 Jan 2003 00:24:34 +0000 Received: from blossom.cjclark.org (localhost. [127.0.0.1]) by blossom.cjclark.org (8.12.6/8.12.3) with ESMTP id h0L0OWeq036170; Mon, 20 Jan 2003 16:24:33 -0800 (PST) (envelope-from crist.clark@attbi.com) Received: (from cjc@localhost) by blossom.cjclark.org (8.12.6/8.12.6/Submit) id h0L0OSuT036169; Mon, 20 Jan 2003 16:24:28 -0800 (PST) X-Authentication-Warning: blossom.cjclark.org: cjc set sender to crist.clark@attbi.com using -f Date: Mon, 20 Jan 2003 16:24:28 -0800 From: "Crist J. Clark" To: Anthony Schneider Cc: David Schultz , zhuravlev alexander , Oleg Shevtsov , security@FreeBSD.ORG Subject: Re: your mail Message-ID: <20030121002428.GF34751@blossom.cjclark.org> Reply-To: "Crist J. Clark" References: <20030120101323.GA371@interexc.com> <20030120102235.GA45357@hp.ulstu.ru> <20030120225609.GB3668@HAL9000.homeunix.com> <20030120235152.GA20708@x-anthony.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030120235152.GA20708@x-anthony.com> User-Agent: Mutt/1.4i X-URL: http://people.freebsd.org/~cjc/ Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Mon, Jan 20, 2003 at 06:51:52PM -0500, Anthony Schneider wrote: > statically linked? is /sbin/nologin not a shell script anymore? It is, but it invokes /bin/sh which is static and calls it with '-p'. > On Mon, Jan 20, 2003 at 02:56:09PM -0800, David Schultz wrote: > > Thus spake zhuravlev alexander : > > > On Mon, Jan 20, 2003 at 12:13:23PM +0200, Oleg Shevtsov wrote: > > > > > > > > Hi, > > > > how to give specific user FTP but no shell access? > > > > Ftpd's manual says: > > > > 4. The user must have a standard shell returned by > > > > getusershell(3). > > > > But I don't want to give shell account. > > > > > > /sbin/nologin ? > > > > If you do it this way, you need to ensure that either the > > ``FTP-only'' users do not have home directories or that > > /sbin/nologin is statically linked (the default). Otherwise, it > > is possible to exploit a bug (ahem, feature) in OpenSSH to gain > > shell access on your box. -- Crist J. Clark | cjclark@alum.mit.edu | cjclark@jhu.edu http://people.freebsd.org/~cjc/ | cjc@freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message