FreeBSD Security Advisory FreeBSD-SA-13:09.ip_multicast

Fabricante: FreeBSD
Fecha: 22/08/2013
Identificador: FreeBSD-SA-13:09.ip
FreeBSD Security Advisory FreeBSD-SA-13:09.ip_multicast
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 FreeBSD-SA-13:09.ip_multicast Security Advisory The FreeBSD Project Topic: integer overflow in IP_MSFILTER Category: core Module: kernel Announced: 2013-08-22 Credits: Clement Lecigne (Google Security Team) Affects: All supported versions of FreeBSD. Corrected: 2013-08-22 00:51:37 UTC (stable/9, 9.2-PRERELEASE) 2013-08-22 00:51:43 UTC (releng/9.2, 9.2-RC2-p1) 2013-08-22 00:51:48 UTC (releng/9.1, 9.1-RELEASE-p6) 2013-08-22 00:51:37 UTC (stable/8, 8.4-STABLE) 2013-08-22 00:51:56 UTC (releng/8.4, 8.4-RELEASE-p3) 2013-08-22 00:51:56 UTC (releng/8.3, 8.3-RELEASE-p10) CVE Name: CVE-2013-3077 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background IP multicast is a method of sending Internet Protocol (IP) datagrams to a group of interested receivers in a single transmission. II. Problem Description An integer overflow in computing the size of a temporary buffer can result in a buffer which is too small for the requested operation. III. Impact An unprivileged process can read or write pages of memory which belong to the kernel. These may lead to exposure of sensitive information or allow privilege escalation. IV. Workaround No workaround is available. V. Solution Perform one of the following: 1) Upgrade your vulnerable system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date. 2) To update your vulnerable system via a source code patch: The following patches have been verified to apply to the applicable FreeBSD release branches. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. # fetch http://security.FreeBSD.org/patches/SA-13:09/ip_multicast.patch # fetch http://security.FreeBSD.org/patches/SA-13:09/ip_multicast.patch.asc # gpg --verify ip_multicast.patch.asc b) Apply the patch. # cd /usr/src # patch < /path/to/patch c) Recompile your kernel as described in and reboot the system. 3) To update your vulnerable system via a binary patch: Systems running a RELEASE version of FreeBSD on the i386 or amd64 platforms can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/8/ r254629 releng/8.3/ r254632 releng/8.4/ r254632 stable/9/ r254629 releng/9.1/ r254631 releng/9.2/ r254630 - ------------------------------------------------------------------------- To see which files were modified by a particular revision, run the following command, replacing XXXXXX with the revision number, on a machine with Subversion installed: # svn diff -cXXXXXX --summarize svn://svn.freebsd.org/base Or visit the following URL, replacing XXXXXX with the revision number: VII. References The latest revision of this advisory is available at -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.21 (FreeBSD) iEYEARECAAYFAlIVY1YACgkQFdaIBMps37K1cwCeOwXryun/C0EceD7v1se+z8w1 EUYAoJ7Hh/bOjyuD6oR6ZOEqtDVIL5LP =6Ehk -----END PGP SIGNATURE-----