CVE-2019-5608

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-19:19.mldv2 Security Advisory The FreeBSD Project Topic: ICMPv6 / MLDv2 out-of-bounds memory access Category: core Module: net Announced: 2019-08-06 Credits: CJD of Apple Affects: All supported versions of FreeBSD. Corrected: 2019-08-06 17:13:41 UTC (stable/12, 12.0-STABLE) 2019-08-06 17:11:17 UTC (releng/12.0, 12.0-RELEASE-p9) 2019-08-06 17:15:46 UTC (stable/11, 11.3-STABLE) 2019-08-06 17:11:17 UTC (releng/11.3, 11.3-RELEASE-p2) 2019-08-06 17:11:17 UTC (releng/11.2, 11.2-RELEASE-p13) CVE Name: CVE-2019-5608 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background 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. IV. Workaround No workaround is available. Systems not using IPv6 are not affected. V. Solution Perform one of the following: Upgrade your vulnerable system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date, and reboot. 1) 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 # shutdown -r +10min “Reboot for security update” 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. [FreeBSD 11.2, FreeBSD 11.3] # fetch https://security.FreeBSD.org/patches/SA-19:19/mldv2.11.patch # fetch https://security.FreeBSD.org/patches/SA-19:19/mldv2.11.patch.asc # gpg --verify mldv2.11.patch.asc [FreeBSD 12.0] # fetch https://security.FreeBSD.org/patches/SA-19:19/mldv2.12.patch # fetch https://security.FreeBSD.org/patches/SA-19:19/mldv2.12.patch.asc # gpg --verify mldv2.12.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 and reboot the system. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/12/ r350648 releng/12.0/ r350644 stable/11/ r350650 releng/11.3/ r350644 releng/11.2/ r350644 - ------------------------------------------------------------------------- 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: VII. References The latest revision of this advisory is available at -----BEGIN PGP SIGNATURE----- iQKTBAEBCgB9FiEE/A6HiuWv54gCjWNV05eS9J6n5cIFAl1Jt1RfFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldEZD MEU4NzhBRTVBRkU3ODgwMjhENjM1NUQzOTc5MkY0OUVBN0U1QzIACgkQ05eS9J6n 5cLzTA/+OyyukXWH7rfwMhOlpD60UH4hxN3purvdNeBe4ZxlYvtf8gSUzS1VbK5r NR9D2HiYRlmaePOil5myan6cVkrKoANoWTrQsCcsFLe6KKbiKlQDx/btbENmCMsR VoS0ZPx3l9iGuVUwDk6k1JXwKCcO3U3dCDYEI941hEKxYadR+twUP3JOceg8Zn0h oODXW7LcPXWQKAyFc0Kun1VrjrUGdRGfqk30joR20GP2IjgQceFHKUbiOyBbbIjW +UVvp2wPBxXvcXNPTpcIpTW5UGJBHCT2OsDulh7hqpiWf78VE8BoksKAvDjtI4i0 15fmwn7tmQ3aGWK3WoaKWUOXZUlKrxRQDzGyAZ3LzOqPWhv12tJjNJhjnRmCVLfo +F4I/MHzPgjitZhv8gfn+MRiPG4E1ueAYnPQWiR3qRCLQGhemVdKZIAVnYg6NGpQ Jgsr1QS8/3GHZ8yrMXUOSNOSuiMmRHbI9915vVzu+hWkfnrCcSr3uVkJeQvx4CZJ gdTL083Knnkdo4IPOdHWnQjGfrv2rGRyvCJ88m/DIC6hw4weR1LyFWMEHeJCEcJl 5LHiVWmOUJE4ltJXrRoXwxuh9Dia0Mq6KfNA0343JFpQF9rdt3JQ/54FPGtK6NUO LyX5a42RIKRxWNTN+ADrSk8czbHFIg8MfTwpjiRGx2rYtxjp1qU= =WaXC -----END PGP SIGNATURE-----