From owner-freebsd-security@FreeBSD.ORG Thu May 1 14:19:56 2014 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 255D8FBC for ; Thu, 1 May 2014 14:19:56 +0000 (UTC) Received: from mail.tdx.com (mail.tdx.com [62.13.128.18]) by mx1.freebsd.org (Postfix) with ESMTP id C0CAB10FD for ; Thu, 1 May 2014 14:19:55 +0000 (UTC) Received: from study64.tdx.co.uk (study64.tdx.co.uk [62.13.130.231]) (authenticated bits=0) by mail.tdx.com (8.14.3/8.14.3/) with ESMTP id s41EJlnv087952 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Thu, 1 May 2014 15:19:47 +0100 (BST) Date: Thu, 01 May 2014 15:19:47 +0100 From: Karl Pielorz To: freebsd-security@freebsd.org Subject: Re: FreeBSD Security Advisory FreeBSD-SA-14:08.tcp Message-ID: <7A880FB5C3D1DA39692881FE@study64.tdx.co.uk> In-Reply-To: <201404300435.s3U4ZAw1093717@freefall.freebsd.org> References: <201404300435.s3U4ZAw1093717@freefall.freebsd.org> X-Mailer: Mulberry/4.0.8 (Mac OS X) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 May 2014 14:19:56 -0000 --On 30 April 2014 04:35:10 +0000 FreeBSD Security Advisories wrote: > II. Problem Description > > FreeBSD may add a reassemble queue entry on the stack into the segment > list when the reassembly queue reaches its limit. The memory from the > stack is undefined after the function returns. Subsequent iterations of > the reassembly function will attempt to access this entry. Hi, Does this require an established TCP session to be present? - i.e. If you have a host which provides no external TCP sessions (i.e. replies 'Connection Refused' / drops the initial SYN) would that still be potentially exploitable? What about boxes used as routers - that just forward the traffic (and again, offer no TCP services directly themselves)? -Karl