From owner-freebsd-security@freebsd.org Wed Aug 7 17:06:20 2019 Return-Path: Delivered-To: freebsd-security@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 623B3B13EF for ; Wed, 7 Aug 2019 17:06:20 +0000 (UTC) (envelope-from mike@sentex.net) Received: from pyroxene.sentex.ca (unknown [IPv6:2607:f3e0:0:3::18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "pyroxene.sentex.ca", Issuer "Let's Encrypt Authority X3" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 463dFS1z0Kz41t2 for ; Wed, 7 Aug 2019 17:06:20 +0000 (UTC) (envelope-from mike@sentex.net) Received: from [192.168.43.26] ([192.168.43.26]) by pyroxene.sentex.ca (8.15.2/8.15.2) with ESMTP id x77H6ITg057233 for ; Wed, 7 Aug 2019 13:06:18 -0400 (EDT) (envelope-from mike@sentex.net) Subject: Re: FreeBSD Security Advisory FreeBSD-SA-19:19.mldv2 To: freebsd-security@freebsd.org References: <20190806183211.EE35BEE16@freefall.freebsd.org> From: Mike Tancsa Openpgp: preference=signencrypt Autocrypt: addr=mike@sentex.net; prefer-encrypt=mutual; keydata= mQENBEzcA24BCACpwI/iqOrs0GfQSfhA1v6Z8AcXVeGsRyKEKUpxoOYxXWc2z3vndbYlIP6E YJeifzKhS/9E+VjhhICaepLHfw865TDTUPr5D0Ed+edSsKjlnDtb6hfNJC00P7eoiuvi85TW F/gAxRY269A5d856bYrzLbkWp2lKUR3Bg6NnORtflGzx9ZWAltZbjYjjRqegPv0EQNYcHqWo eRpXilEo1ahT6nmOU8V7yEvT2j4wlLcQ6qg7w+N/vcBvyd/weiwHU+vTQ9mT61x5/wUrQhdw 2gJHeQXeDGMJV49RT2EEz+QVxaf477eyWsdQzPVjAKRMT3BVdK8WvpYAEfBAbXmkboOxABEB AAG0HG1pa2UgdGFuY3NhIDxtaWtlQHNlbnRleC5jYT6JATgEEwECACIFAkzcA24CGwMGCwkI BwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEJXHwM2kc8rX+sMH/2V6pTBKsQ5mpWWLgs6wVP2k BC+6r/YKNXv9Rw/PrC6+9hTbgA+sSjJ+8gxsCbJsOQXZrxF0x3l9oYdYfuKcwdwXFX1/FS8p HfBeDkmlH+dI709xT9wgrR4dS5aMmKp0scPrXPIAKiYVOHjOlNItcLYTEEWEFBepheEVsgmk GrNbcrHwOx/u4igUQ8vcpyXPyUki+BsftPw8ZQvBU887igh0OxaCR8AurJppQ5UQd63r81cX E1ZjoFoWCaGK/SjPb/OhpYpu5swoZIhOxQbn7OtakYPsDd5t2A5KhvjI8BMTnd5Go+2xsCmr jlIEq8Bi29gCcfQUvNiClevi13ifmnm5AQ0ETNwDbgEIALWGNJHRAhpd0A4vtd3G0oRqMBcM FGThQr3qORmEBTPPEomTdBaHcn+Xl+3YUvTBD/67/mutWBwgp2R5gQOSqcM7axvgMSHbKqBL 9sd1LsLw0UT2O5AYxv3EwzhG84pwRg3XcUqvWA4lA8tIj/1q4Jzi5qOkg1zxq4W9qr9oiYK5 bBR638JUvr3eHMaz/Nz+sDVFgwHmXZj3M6aE5Ce9reCGbvrae7H5D5PPvtT3r22X8SqfVAiO TFKedCf/6jbSOedPN931FJQYopj9P6b3m0nI3ZiCDVSqeyOAIBLzm+RBUIU3brzoxDhYR8pz CJc2sK8l6YjqivPakrD86bFDff8AEQEAAYkBHwQYAQIACQUCTNwDbgIbDAAKCRCVx8DNpHPK 1+iQB/99aqNtez9ZTBWELj269La8ntuRx6gCpzfPXfn6SDIfTItDxTh1hrdRVP5QNGGF5wus N4EMwXouskva1hbFX3Pv72csYSxxEJXjW16oV8WK4KjKXoskLg2RyRP4uXqL7Mp2ezNtVY5F 9nu3fj4ydpHCSaqKy5xd70A8D50PfZsFgkrsa5gdQhPiGGEdxhq/XSeAAnZ4uVLJKarH+mj5 MEhgZPEBWkGrbDZpezl9qbFcUem/uT9x8FYT/JIztMVh9qDcdP5tzANW5J7nvgXjska+VFGY ryZK4SPDczh74mn6GI/+RBi7OUzXXPgpPBrhS5FByjwCqjjsSpTjTds+NGIY Organization: Sentex Communications Message-ID: Date: Wed, 7 Aug 2019 13:06:17 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190806183211.EE35BEE16@freefall.freebsd.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Language: en-US X-Rspamd-Queue-Id: 463dFS1z0Kz41t2 X-Spamd-Bar: ------ Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-6.98 / 15.00]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; NEURAL_HAM_LONG(-1.00)[-0.995,0]; REPLY(-4.00)[]; NEURAL_HAM_SHORT(-0.98)[-0.981,0] X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 07 Aug 2019 17:06:20 -0000 Does anyone have any more details about the implication of this ? e.g. does a daemon need to be listening on a target device ? Is it merely the act of forwarding such packets ? Can a non root user open such a daemon ? Thanks,     ---Mike > ============================================================================= > FreeBSD-SA-19:19.mldv2                                      Security > Advisory >                                                           The FreeBSD > Project > > Topic:          ICMPv6 / MLDv2 out-of-bounds memory access > MLDv2 is the Multicast Listener Discovery protocol, version 2.  It is used > by IPv6 routers to discover multicast listeners. > > II.  Problem Description > > The ICMPv6 input path incorrectly handles cases where an MLDv2 listener > query packet is internally fragmented across multiple mbufs. > > III. Impact > > A remote attacker may be able to cause an out-of-bounds read or write that > may cause the kernel to attempt to access an unmapped page and > subsequently > panic.