From owner-freebsd-security Mon Nov 16 11:32:09 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id LAA25959 for freebsd-security-outgoing; Mon, 16 Nov 1998 11:32:09 -0800 (PST) (envelope-from owner-freebsd-security@FreeBSD.ORG) Received: from weathership.homeport.org (weathership.homeport.org [207.31.235.99]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id LAA25876 for ; Mon, 16 Nov 1998 11:32:03 -0800 (PST) (envelope-from adam@weathership.homeport.org) Received: (from adam@localhost) by weathership.homeport.org (8.8.8/8.8.5) id OAA11731; Mon, 16 Nov 1998 14:45:57 -0500 (EST) Message-ID: <19981116144556.A11685@weathership.homeport.org> Date: Mon, 16 Nov 1998 14:45:56 -0500 From: Adam Shostack To: Robert Watson , Thomas Valentino Crimi Cc: Terry Lambert , freebsd-security@FreeBSD.ORG Subject: Re: Would this make FreeBSD more secure? References: <0qI4qUS00YUq09JbU0@andrew.cmu.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.93i In-Reply-To: ; from Robert Watson on Mon, Nov 16, 1998 at 12:46:24PM -0500 Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org My understanding of Dobbertin's attack is that he generates both halves of a collision pair, not finds an arbitrary match to a pre-existing value. If he has the latter, that may or may not transform into an attack on the password system. You'll need to find a printable (<9 character?) value that collides if you want to attack the password system via this route. Adam On Mon, Nov 16, 1998 at 12:46:24PM -0500, Robert Watson wrote: | On Mon, 16 Nov 1998, Thomas Valentino Crimi wrote: | > And then we have md5 passwords, arguably broken, now, but orders of | > magnitudes better than DES. | | I don't think I would consider md5 broken exactly. Just subject to | intermittent collisions. Is there a deterministic (and fast) way to | detect whether one is employing a hash subject to the described collision | attack? If so, perhaps we can add a piece of code that attempts a number | of values of salt, resulting in a more friendly hash. | | I prefer one-time passwords for security applications; on the other hand I | eagerly await a nice (scalable) PK authentication system used with | hardware keys. -- "It is seldom that liberty of any kind is lost all at once." -Hume To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message