From owner-freebsd-security@FreeBSD.ORG Tue May 5 02:49:13 2015 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 7756B1AC for ; Tue, 5 May 2015 02:49:13 +0000 (UTC) Received: from vps1.elischer.org (vps1.elischer.org [204.109.63.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "vps1.elischer.org", Issuer "CA Cert Signing Authority" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 2F26F1A33 for ; Tue, 5 May 2015 02:49:12 +0000 (UTC) Received: from Julian-MBP3.local (ppp121-45-241-118.lns20.per4.internode.on.net [121.45.241.118]) (authenticated bits=0) by vps1.elischer.org (8.14.9/8.14.9) with ESMTP id t452n7lJ027815 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Mon, 4 May 2015 19:49:10 -0700 (PDT) (envelope-from julian@freebsd.org) Message-ID: <55482F9E.8050701@freebsd.org> Date: Tue, 05 May 2015 10:49:02 +0800 From: Julian Elischer User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Mike Tancsa , "freebsd-security@freebsd.org" Subject: Re: SA-14:19 (Denial of Service in TCP packet processing) and jails issue ? References: <5541560C.5020004@sentex.net> <5547E47A.5040502@sentex.net> In-Reply-To: <5547E47A.5040502@sentex.net> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 May 2015 02:49:13 -0000 On 5/5/15 5:28 AM, Mike Tancsa wrote: > On 4/29/2015 6:07 PM, Mike Tancsa wrote: >> >> The IP being scanned is in a jail. If I run the scan to an IP not >> associated with the jail, the scan does not complain. Its only on the >> jailed IP that the scan flags as problematic for this vulnerability. >> >> If this is a false positive, how can I be sure thats the case ? I have >> pcaps of the scan both against the jailed IP (with the scan saying its >> vulnerable) and against an IP not associated with the jail, saying its >> not an issue. >> > > > Anyone have any have any ideas what can be done to mitigate this > risk if its real, or if its a false positive ? Firstly I assume you are not talking about a vimage jail? It seems unlikely that jailing affects that processing. Does the test actually try cause the problem to occur? a tcpdump would be really nice. > > To further clarify/describe my test environment, this is a RELENG_9 > box I am testing against. I have a number of IPs aliased to lo0 > associated with jails. If I run the Qualsys scan against an IP on > this box that is not associated with a jail, it passes the test for > SA-14:19. If I run the test against an IP associated with the jail, > it fails the test. > > e.g. IP 192.168.1.1 is aliased to lo0 and associated with > jail1.sentex.ca. > > If I run the free qualsys scan against jail1.sentex.ca, the test > fails. If I stop the jail, and run the qualsys scan against the > same IP, which is now just an aliased IP on the host machine, it > passes the test. I have the pcaps, but I am not sure exactly what I > am looking for in the data. The test just says it confirmed the > vulnerability with the following 2 tests, > > Tested on port 22 with an injected SYN/RST offset by 16 bytes. > Tested on port 25 with an injected SYN/RST offset by 16 bytes. > > What is it about the jail that might be causing either this issue to > resurface, or give a false positive that its an issue ? > > > ---Mike > > >