From owner-freebsd-security@FreeBSD.ORG Thu Jan 7 00:37:41 2010 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 26FFD1065698 for ; Thu, 7 Jan 2010 00:37:41 +0000 (UTC) (envelope-from Harlan.Stenn@pfcs.com) Received: from gwc.pfcs.com (gwc.pfcs.com [70.88.151.226]) by mx1.freebsd.org (Postfix) with ESMTP id EE0468FC19 for ; Thu, 7 Jan 2010 00:37:40 +0000 (UTC) Received: from spike.pfcs.com (localhost.pfcs.com [127.0.0.1]) by gwc.pfcs.com (Postfix) with ESMTP id 36C8128438; Wed, 6 Jan 2010 19:18:20 -0500 (EST) To: freebsd-security@freebsd.org From: Harlan Stenn In-Reply-To: FreeBSD Security Advisories's (security-advisories@freebsd.org) message dated Wed, 06 Jan 2010 22:55:36. <201001062255.o06MtanW089116@freefall.freebsd.org> X-Face: "csXK}xnnsH\h_ce`T#|pM]tG, 6Xu.{3Rb\]&XJgVyTS'w{E+|-(}n:c(Cc* $cbtusxDP6T)Hr'k&zrwq0.3&~bAI~YJco[r.mE+K|(q]F=ZNXug:s6tyOk{VTqARy0#axm6BWti9C d X-Mailer: MH-E 7.4.2; nmh 1.2; XEmacs 21.4 (patch 22) Mime-Version: 1.0 (generated by tm-edit 1.8) Content-Type: text/plain; charset=US-ASCII Date: Wed, 06 Jan 2010 19:18:20 -0500 Sender: Harlan.Stenn@pfcs.com Message-Id: <20100107001820.36C8128438@gwc.pfcs.com> X-Mailman-Approved-At: Thu, 07 Jan 2010 00:49:29 +0000 Cc: stenn@ntp.org Subject: Re: [FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-10:02.ntpd X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 Jan 2010 00:37:41 -0000 Not quite... > II. Problem Description > > If ntpd receives a mode 7 (MODE_PRIVATE) request or error response it's a *malformed* mode 7 request, or an error response ... Normal mode 7 requests have been (and are) handled just fine and are not logged by default. > from a source address not listed in either a 'restrict ... noquery' > or a 'restrict ... ignore' section it will log the even and send s/even/event/ > a mode 7 error response. > IV. Workaround > > Proper filtering of mode 7 NTP packets by a firewall can limit the > number of systems used to attack your resources. If you can find a firewall that will do this, please lemme know. We haven't found any. Thanks... H