From owner-freebsd-security Tue May 26 20:18:46 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id UAA01191 for freebsd-security-outgoing; Tue, 26 May 1998 20:18:46 -0700 (PDT) (envelope-from owner-freebsd-security@FreeBSD.ORG) Received: from dc1.mfn.org (dc1.mfn.org [204.238.179.1]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id UAA01170 for ; Tue, 26 May 1998 20:18:32 -0700 (PDT) (envelope-from sysadmin@mfn.org) Received: from w3svcs.mfn.org (unverified [204.238.179.11]) by mail.mfn.org (EMWAC SMTPRS 0.83) with SMTP id ; Tue, 26 May 1998 22:08:19 -0500 Received: by w3svcs.mfn.org with Microsoft Mail id <01BD88F2.6DDD3A40@w3svcs.mfn.org>; Tue, 26 May 1998 22:05:44 -0500 Message-ID: <01BD88F2.6DDD3A40@w3svcs.mfn.org> From: "J.A. Terranson" To: "'FreeBSD Security'" Subject: Possible DoS opportunity via ping implementation error? Date: Tue, 26 May 1998 22:05:42 -0500 Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk I had a very interesting day today! I found out that FBSD (2.2.5R) machines will always respond to a broadcasted echo request. For example: W2>ping 10.1.1.255 PING 10.1.1.255 (10.1.1.255): 56 data bytes 64 bytes from 10.1.1.20: icmp_seq=1 ttl=255 time=4.746 ms 64 bytes from 10.1.1.23: icmp_seq=1 ttl=255 time=45.864 ms (DUP!) lots of these dups... In fact, 1 dup for every FBSD machine on the subnet (interestingly, there were no replies from my NT4.0 boxes...) Since I do not follow the "security" list, please respond directly. Thanks. J.A. Terranson sysadmin@mfn.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe security" in the body of the message