From owner-freebsd-security Sat Jan 23 04:32:47 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id EAA26222 for freebsd-security-outgoing; Sat, 23 Jan 1999 04:32:47 -0800 (PST) (envelope-from owner-freebsd-security@FreeBSD.ORG) Received: from smtp1.xs4all.nl (smtp1.xs4all.nl [194.109.6.51]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id EAA26216 for ; Sat, 23 Jan 1999 04:32:42 -0800 (PST) (envelope-from unicorn@unicorn.xs4all.nl) Received: from unicorn.xs4all.nl (1001@unicorn.xs4all.nl [194.109.83.155]) by smtp1.xs4all.nl (8.8.8/8.8.8) with ESMTP id NAA17810; Sat, 23 Jan 1999 13:32:26 +0100 (CET) Received: (from unicorn@localhost) by unicorn.xs4all.nl (8.8.8/8.8.8) id NAA21827; Sat, 23 Jan 1999 13:26:13 +0100 (CET) (envelope-from unicorn) Message-ID: <19990123132613.A21293@unicorn.quux.org> Date: Sat, 23 Jan 1999 13:26:13 +0100 From: The Unicorn To: Robert Watson , cjclark@home.com Cc: freebsd-security@FreeBSD.ORG Subject: Re: bin Directory Ownership References: <199901230414.XAA02392@cc942873-a.ewndsr1.nj.home.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.93.2i In-Reply-To: ; from Robert Watson on Sat, Jan 23, 1999 at 06:01:40AM -0500 X-GSM: +31 XXX XXX XXX X-Files: The Truth Is Out There! X-RSAkey: http://keys.pgp.com:11371/pks/lookup?op=get&search=0x0A7B84E7 X-DSSkey: http://keys.pgp.com:11371/pks/lookup?op=get&search=0x0BBF4902 X-Copyright-0: Portions of this message may be subject to copyright. X-Copyright-1: (c)1994-1998 Hans "Unicorn" Van de Looy. X-Disclaimer-0: Comments contained do not necessarily represent X-Disclaimer-1: those of my current employer. Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Sat, Jan 23, 1999 at 06:01:40AM -0500, Robert Watson wrote: > > You are correct--there is no security improvement through the use of the > bin user. However, it is also the case that (aside from false assumptions > about some improvement) security is probably not damaged by having a bin > user. I am in the process of some research analyzing the impact of file > and directory ownership affecting the UNIX trust model (especially w.r.t. > setuid and setgid binaries). I will post the results when I finish up > (probably in a month or so). Access to the bin account is very limited; > effectively, to acquire a uid bin process capable of modifying the > binaries, you would first have to have a uid root process that you had > subverted. This is not always the case. Have a look at the old but still valid paper from Wietse and Dan: "admin-guide-to-cracking-101" also known as "Improving the Security of Your Site by Breaking Into it". Especially the part on the use of rsh and the wildcard in the /etc/hosts.equiv file (yeah, I know that allowing the r-commands is a BIG NO-NO ;-). > Robert N Watson ---end quoted text--- Ciao, Unicorn. -- ======= _ __,;;;/ TimeWaster ================================================ ,;( )_, )~\| A Truly Wise Man Never Plays PGP: 64 07 5D 4C 3F 81 22 73 ;; // `--; Leapfrog With A Unicorn... 52 9D 87 08 51 AA 35 F0 ==='= ;\ = | ==== Youth is not a time in Life, It is a State of Mind! ======= To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message