From owner-freebsd-security@FreeBSD.ORG Fri Apr 22 10:20:39 2005 Return-Path: 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 81A7F16A4E3 for ; Fri, 22 Apr 2005 10:20:39 +0000 (GMT) Received: from mailhost.stack.nl (vaak.stack.nl [131.155.140.140]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7F25E43D58 for ; Fri, 22 Apr 2005 10:20:25 +0000 (GMT) (envelope-from dean@dragon.stack.nl) Received: from dragon.stack.nl (dragon.stack.nl [IPv6:2001:610:1108:5011:207:e9ff:fe09:230]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mailhost.stack.nl (Postfix) with ESMTP id 3D4B81F31F; Fri, 22 Apr 2005 12:20:24 +0200 (CEST) Received: by dragon.stack.nl (Postfix, from userid 1600) id 160875F157; Fri, 22 Apr 2005 12:20:24 +0200 (CEST) Date: Fri, 22 Apr 2005 12:20:24 +0200 From: Dean Strik To: Jesper Wallin Message-ID: <20050422102023.GA81889@dragon.stack.nl> References: <42686A29.7090900@hackunite.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <42686A29.7090900@hackunite.net> X-Editor: VIM Rulez! http://www.vim.org/ X-MUD: Outerspace - telnet://mud.stack.nl:3333 X-Really: Yes User-Agent: Mutt/1.5.9i X-Mailman-Approved-At: Fri, 22 Apr 2005 13:45:39 +0000 cc: freebsd-security@freebsd.org Subject: Re: Information disclosure? X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Security issues [members-only posting] List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Apr 2005 10:20:39 -0000 Jesper Wallin wrote: > For some reason, I thought little about the "clear" command today.. > Let's say a privileged user (root) logs on, edit a sensitive file (e.g, > a file containing a password, running vipw, etc) .. then runs clear and > logout. Then anyone can press the scroll-lock command, scroll back up > and read the sensitive information.. Isn't "clear" ment to clear the > backbuffer instead of printing a full screen of returns? If it does, I'm > not sure how that would effect a user running "clear" on a pty (telnet, > sshd, screen, etc) .. vidcontrol -C ; clear -- Dean C. Strik Eindhoven University of Technology dean@stack.nl | dean@ipnet6.org | http://www.ipnet6.org/ "This isn't right. This isn't even wrong." -- Wolfgang Pauli