From owner-freebsd-security@FreeBSD.ORG Thu Mar 23 09:03:34 2006 Return-Path: X-Original-To: FreeBSD-security@freebsd.org Delivered-To: FreeBSD-security@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 73FF016A424 for ; Thu, 23 Mar 2006 09:03:34 +0000 (UTC) (envelope-from dmitry@atlantis.dp.ua) Received: from postman.atlantis.dp.ua (postman.atlantis.dp.ua [193.108.47.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0DDB143D46 for ; Thu, 23 Mar 2006 09:03:27 +0000 (GMT) (envelope-from dmitry@atlantis.dp.ua) Received: from smtp.atlantis.dp.ua (smtp.atlantis.dp.ua [193.108.46.231]) by postman.atlantis.dp.ua (8.13.1/8.13.1) with ESMTP id k2N93AlW002079 for ; Thu, 23 Mar 2006 11:03:10 +0200 (EET) (envelope-from dmitry@atlantis.dp.ua) Date: Thu, 23 Mar 2006 11:03:10 +0200 (EET) From: Dmitry Pryanishnikov To: FreeBSD-security@freebsd.org In-Reply-To: <200603221611.k2MGBNaj010025@freefall.freebsd.org> Message-ID: <20060323110015.R99976@atlantis.atlantis.dp.ua> References: <200603221611.k2MGBNaj010025@freefall.freebsd.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: Subject: Re: FreeBSD Security Advisory FreeBSD-SA-06:11.ipsec 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, 23 Mar 2006 09:03:34 -0000 Hello! On Wed, 22 Mar 2006, FreeBSD Security Advisories wrote: > II. Problem Description > > IPsec provides an anti-replay service which when enabled prevents an attacker > from successfully executing a replay attack. This is done through the > verification of sequence numbers. A programming error in the fast_ipsec(4) > implementation results in the sequence number associated with a Security > Association not being updated, allowing packets to unconditionally pass > sequence number verification checks. > > III. Impact > > An attacker able to to intercept IPSec packets can replay them. If higher > level protocols which do not provide any protection against packet replays > (e.g., UDP) are used, this may have a variety of effects. As far as I understood, only systems which use "options FAST_IPSEC" are affected by this issue. Is it true? If so, wouldn't be wise to stress this fact in the advisory? Sincerely, Dmitry -- Atlantis ISP, System Administrator e-mail: dmitry@atlantis.dp.ua nic-hdl: LYNX-RIPE