-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-15:04.igmp Security Advisory The FreeBSD Project
Topic: Integer overflow in IGMP protocol Category: core Module: igmp Announced: 2015-02-25; Last revised on 2015-04-07 Credits: Mateusz Kocielski, Logicaltrust, Marek Kroemeke, and 22733db72ab3ed94b5f8a1ffcde850251fe6f466 Affects: All supported versions of FreeBSD. Corrected: 2015-04-07 20:20:24 UTC (stable/10, 10.1-STABLE) 2015-04-07 20:21:01 UTC (releng/10.1, 10.1-RELEASE-p9) 2015-04-07 20:20:44 UTC (stable/9, 9.3-STABLE) 2015-04-07 20:21:23 UTC (releng/9.3, 9.3-RELEASE-p13) 2015-04-07 20:20:44 UTC (stable/8, 8.4-STABLE) 2015-04-07 20:21:23 UTC (releng/8.4, 8.4-RELEASE-p27) CVE Name: CVE-2015-1414 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:https://security.FreeBSD.org/>. 0. Revision history v1.0 2015-02-25 Initial release. v1.1 2015-04-07 Revised patch to address a potential overflow issue. I. Background IGMP is a control plane protocol used by IPv4 hosts and routers to propagate multicast group membership information. IGMP version 3 is implemented on FreeBSD. II. Problem Description An integer overflow in computing the size of IGMPv3 data buffer can result in a buffer which is too small for the requested operation. III. Impact An attacker who can send specifically crafted IGMP packets could cause a denial of service situation by causing the kernel to crash. IV. Workaround Block incoming IGMP packets by protecting your host/networks with a firewall. 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 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 3) 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 https://security.FreeBSD.org/patches/SA-15:04/igmp.patch # fetch https://security.FreeBSD.org/patches/SA-15:04/igmp.patch.asc # gpg --verify igmp.patch.asc # fetch https://security.FreeBSD.org/patches/SA-15:04/igmp-errata.patch # fetch https://security.FreeBSD.org/patches/SA-15:04/igmp-errata.patch.asc # gpg --verify igmp-errata.patch.asc b) Apply the patch. Execute the following commands as root: # cd /usr/src # patch < /path/to/patch c) Recompile your kernel as described in <URL:https://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the system. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/8/ r281231 releng/8.4/ r281233 stable/9/ r281231 releng/9.3/ r281233 stable/10/ r281230 releng/10.1/ r281232 - ------------------------------------------------------------------------- To see which files were modified by a particular revision, run the following command, replacing NNNNNN with the revision number, on a machine with Subversion installed: # svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base Or visit the following URL, replacing NNNNNN with the revision number: <URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN> VII. References <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1414> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-15:04.igmp.asc> -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.1.2 (FreeBSD) iQIcBAEBCgAGBQJVJD39AAoJEO1n7NZdz2rnewwQAN9xI01nzOO71Q7qP7xDq+wu RW2C+2A4viIZIId1od6GiDY7Qpigy1CMwHsae6qJ62R+D5F2x9vANV4U6AS44oNy 2jDwbrByM7QQ3qeCh8NzCUvOwPuXyKsAGKV73t3QPk0leKdbqUyjTooWJtZAv0dN VgQ4VCQh+2ZlxjMT0igUScmCVqOncRUm33xKBLeTif5LZHi/afkR6CToMlACOvl3 syJNhEeM+zYU9XLzb90hAjvqn1xLDkoS4qJNbrekj0/dI0jkgZdk18QAualwWgeZ i39Da6IQ4wCn8Sx9o8pc8NdtzHn37rmOcdzBIodzxa1vALmNhDWuBpIIysffsZvf ewVdI83pabRdZZxO1YAPjJi34CTXmvwf8Hit/hh0n1AO21lhr0NhwQzEn7gmLqSh JZYg46k6tNGy6qUa1NU/ywja0kLCG0KdR1FO9IKaN6TCgB30bpndGq1Y0esX1Mo8 5xq/P/KoNPE9BzifyhbDBt77eEmfpiKIuQXQVP3B1n3KEDDUlSSeiz3x0h9ZOjfm vLb1hinfp1RPC4S72a0Zts6r60aee9dMWd/DvC8RqWQqEE0PUamipL2ClzBmOpTK F9b2y9776hfPV/mvGUwS7H63mAMJkMOTDGZn3WWIT3Dmr6Eru0/t1XXqCPB4cNUl uf5sxNtEDjXadkeM20lu =y2yR -----END PGP SIGNATURE-----