From owner-freebsd-announce Mon Aug 27 14:45: 9 2001 Delivered-To: freebsd-announce@freebsd.org Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id 5CCFF37B407; Mon, 27 Aug 2001 14:44:57 -0700 (PDT) (envelope-from security-advisories@FreeBSD.org) Received: (from kris@localhost) by freefall.freebsd.org (8.11.4/8.11.4) id f7RLivL71152; Mon, 27 Aug 2001 14:44:57 -0700 (PDT) (envelope-from security-advisories@FreeBSD.org) Date: Mon, 27 Aug 2001 14:44:57 -0700 (PDT) Message-Id: <200108272144.f7RLivL71152@freefall.freebsd.org> X-Authentication-Warning: freefall.freebsd.org: kris set sender to security-advisories@FreeBSD.org using -f From: FreeBSD Security Advisories To: FreeBSD Security Advisories Subject: FreeBSD Security Advisory FreeBSD-SA-01:57.sendmail Reply-To: security-advisories@FreeBSD.org Sender: owner-freebsd-announce@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org -----BEGIN PGP SIGNED MESSAGE----- ============================================================================= FreeBSD-SA-01:57 Security Advisory FreeBSD, Inc. Topic: sendmail contains local root vulnerability Category: core Module: sendmail Announced: 2001-08-27 Credits: Cade Cairnss Affects: FreeBSD 4-STABLE after August 27, 2000 and prior to the correction date, FreeBSD 4.1.1-RELEASE, 4.2-RELEASE, 4.3-RELEASE Corrected: 2001-08-21 01:36:37 UTC (FreeBSD 4.3-STABLE) 2001-08-22 05:34:11 UTC (RELENG_4_3) FreeBSD only: NO I. Background sendmail is a mail transfer agent. II. Problem Description Sendmail contains an input validation error which may lead to the execution of arbitrary code with elevated privileges by local users. Due to the improper use of signed integers in code responsible for the processing of debugging arguments, a local user may be able to supply the signed integer equivalent of a negative value supplied to sendmail's "trace vector". This may allow a local user to write data anywhere within a certain range of locations in process memory. Because the '-d' command-line switch is processed before the program drops its elevated privileges, the attacker may be able to cause arbitrary code to be executed with root privileges. III. Impact Local users may be able to execute arbitrary code with root privileges. IV. Workaround Do not allow untrusted users to execute the sendmail binary. V. Solution One of the following: 1) Upgrade your vulnerable FreeBSD system to 4.3-STABLE or the RELENG_4_3 security branch after the respective correction dates. 2) FreeBSD 4.x systems after August 27, 2000 and prior to the correction date: The following patch has been verified to apply to FreeBSD 4.1.1-RELEASE, 4.2-RELEASE, 4.3-RELEASE and 4-STABLE dated prior to the correction date. Download the patch and the detached PGP signature from the following locations, and verify the signature using your PGP utility. # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-01:57/sendmail.patch # fetch ftp://ftp.freebsd.org/pub/FreeBSD/CERT/patches/SA-01:57/sendmail.patch.asc Execute the following commands as root: # cd /usr/src # patch -p < /path/to/patch # cd /usr/src/lib/libsmutil # make depend && make all # cd /usr/src/usr.sbin/sendmail # make depend && make all install 3) FreeBSD 4.3-RELEASE systems: An experimental upgrade package is available for users who wish to provide testing and feedback on the binary upgrade process. This package may be installed on FreeBSD 4.3-RELEASE systems only, and is intended for use on systems for which source patching is not practical or convenient. If you use the upgrade package, feedback (positive or negative) to security-officer@FreeBSD.org is requested so we can improve the process for future advisories. During the installation procedure, backup copies are made of the files which are replaced by the package. These backup copies will be reinstalled if the package is removed, reverting the system to a pre-patched state. # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/packages/SA-01:57/security-patch-sendmail-01.57.tgz # fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/CERT/packages/SA-01:57/security-patch-sendmail-01.57.tgz.asc Verify the detached PGP signature using your PGP utility. # pkg_add security-patch-sendmail-01:57.tgz Restart sendmail after applying the patch by executing the following commands as root: # killall sendmail # /usr/sbin/sendmail -bd -q30m The flags to sendmail may need to be adjusted as required for the local system configuration. VI. Correction details The following is the sendmail $Id$ revision number of the file that was corrected for the supported branches of FreeBSD. The $Id$ revision number of the installed source can be examined using the ident(1) command. Revision Path 8.20.22.4 src/contrib/sendmail/src/trace.c VII. References -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: For info see http://www.gnupg.org iQCVAwUBO4q+6lUuHi5z0oilAQH2xQP/e5UR1/UiVoNLjWnZr/3Ufk11/Dx0jeux W43znQ3Hae7ZDK17bUvvJ0t3uSq7mgzP1EmHYhjWWvrVNOaKLNO2C7oiTBWeyNWj J+hk26jZQO74mQDdZVwIr4SbE+tMTUIfEcVcXv7++ZS3xbyh3wyQKZipD5UElnLs ek/7MzKM83E= =Lv0A -----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