From owner-freebsd-announce Sat Feb 19 22:42:36 2000 Delivered-To: freebsd-announce@freebsd.org Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21]) by hub.freebsd.org (Postfix) with ESMTP id 5426437BE84; Sat, 19 Feb 2000 22:42:28 -0800 (PST) (envelope-from security-officer@freebsd.org) Received: (from kris@localhost) by freefall.freebsd.org (8.9.3/8.9.2) id WAA10401; Sat, 19 Feb 2000 22:42:28 -0800 (PST) (envelope-from security-officer@freebsd.org) Date: Sat, 19 Feb 2000 22:42:28 -0800 (PST) Message-Id: <200002200642.WAA10401@freefall.freebsd.org> X-Authentication-Warning: freefall.freebsd.org: kris set sender to security-officer@freebsd.org using -f From: FreeBSD Security Officer Subject: FreeBSD Security Advisory: FreeBSD-SA-00:03.asmon Reply-To: security-officer@freebsd.org From: FreeBSD Security Officer Sender: owner-freebsd-announce@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org -----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-00:03 Security Advisory FreeBSD, Inc. Topic: Asmon/Ascpu ports fail to drop privileges Category: ports Module: asmon/ascpu Announced: 2000-02-19 Affects: Ports collection before the correction date. Corrected: 2000-01-29 FreeBSD only: yes I. Background Two optional third-party ports distributed with FreeBSD can be used to execute commands with elevated privileges, specifically setgid kmem privileges. This may lead to a local root compromise. II. Problem Description Asmon and ascpu allow users to execute arbitrary commands as part of a user configuration file. Both applications are Linux-centric as distributed by the vendor and require patching to run under FreeBSD (specifically, using the kvm interface and setgid kmem privileges to obtain system statistics); this patching was the source of the present security problem. This is a similar flaw to one found in the wmmon port, which was corrected on 1999/12/31. Note that neither utility is installed by default, nor are they "part of FreeBSD" as such: they are part of the FreeBSD ports collection, which contains over 3100 third-party applications in a ready-to-install format. FreeBSD makes no claim about the security of these third-party applications, although an effort is underway to provide a security audit of the most security-critical ports. III. Impact If you have not chosen to install the asmon or ascpu ports/packages, then your system is not vulnerable. If you have, then local users can obtain setgid kmem rights, which allows them to manipulate kernel memory, and thereby compromise root. IV. Workaround Remove the asmon and ascpu ports/packages, if you have installed them. V. Solution One of the following: 1) Upgrade your entire ports collection and rebuild the asmon and/or ascpu ports. 2) Reinstall a new package obtained from: ftp://ftp.freebsd.org/pub/FreeBSD/ports/packages/sysutils/asmon-0.60.tgz ftp://ftp.freebsd.org/pub/FreeBSD/ports/packages/sysutils/ascpu-1.8.tgz after the correction date. At the time of advisory release, the asmon package was not available - you may need to use one of the other methods to update the software. 3) download a new port skeleton for the asmon and/or ascpu ports from: http://www.freebsd.org/ports/ and use it to rebuild one or both ports. 4) Use the portcheckout utility to automate option (3) above. The portcheckout port is available in /usr/ports/devel/portcheckout or the package can be obtained from: ftp://ftp.freebsd.org/pub/FreeBSD/ports/packages/devel/portcheckout-2.0.tgz -----BEGIN PGP SIGNATURE----- Version: 2.6.2 iQCVAwUBOK+LsFUuHi5z0oilAQHRZAP+MC3e3NhGNTDhiL/GAQjewUS8c16ClPhj WruCd5Tu1WJA2Em8Q19Ui7vrLRLQ9aXzTocUOBd6x6/zqpM3lS1aJMwvV9BkZ59G ONh6aiM7FbWPKukW1YThKDn0Vjtc5JaDHsbJ4dVHQh/IMqZD8hqocLG4AjJDxnLj qlRyhiCr/lA= =l1gj -----END PGP SIGNATURE----- This is the moderated mailing list freebsd-announce. The list contains announcements of new FreeBSD capabilities, important events and project milestones. See also the FreeBSD Web pages at http://www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-announce" in the body of the message