From owner-freebsd-security Thu Jan 27 16:22: 8 2000 Delivered-To: freebsd-security@freebsd.org Received: from lariat.lariat.org (lariat.lariat.org [206.100.185.2]) by hub.freebsd.org (Postfix) with ESMTP id E01CB14E71 for ; Thu, 27 Jan 2000 16:22:04 -0800 (PST) (envelope-from brett@lariat.org) Received: from mustang (IDENT:ppp0.lariat.org@lariat.lariat.org [206.100.185.2]) by lariat.lariat.org (8.9.3/8.9.3) with ESMTP id RAA12459; Thu, 27 Jan 2000 17:21:56 -0700 (MST) Message-Id: <4.2.2.20000127171529.00c56a00@localhost> X-Sender: brett@localhost X-Mailer: QUALCOMM Windows Eudora Pro Version 4.2.2 Date: Thu, 27 Jan 2000 17:21:50 -0700 To: Matthew Dillon From: Brett Glass Subject: Re: Riddle me this Cc: security@FreeBSD.ORG In-Reply-To: <200001270425.UAA18744@apollo.backplane.com> References: <200001270355.UAA01355@lariat.lariat.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org At 09:25 PM 1/26/2000 , Matthew Dillon wrote: > It's hard to say without doing a continuous tcpdump but the most likely > possibility is that someone was playing a game or doing something else > related to sending and receiving UDP packets, and then disconnected. Actually, I think I just found out what it was. Two words: HP JetAdmin. Apparently, some people at the site just got a new JetDirect print server. When you install the client software, it sets itself up -- by default -- to test EVERY IP ADDRESS IN THE SUBNET to see if it has an HP print server on it. And it gets worse. The default address of the print server hardware -- which the client software tries to reach when it's setting up -- is (are you ready?) 192.0.0.192. This isn't a legal address, nor is it a standard "unregistered" address for a private subnet. So, natd tries to route it. We really ought to block this by default by putting a "black hole" entry in the system routing table. It certainly should not ever be routed.... Cisco routers automatically blackhole it. --Brett To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message