FreeBSD Security Advisory FreeBSD-SA-15:05.bind
25 February, 2015 by security-advisories@freebsd.org | freebsd
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-15:05.bind Security Advisory The FreeBSD Project Topic: BIND remote denial of service vulnerability Category: contrib Module: bind Announced: 2015-02-25 Credits: ISC Affects: FreeBSD 8.x and FreeBSD 9.x. Corrected: 2015-02-18 22:20:19 UTC (stable/9, 9.3-STABLE) 2015-02-25 05:56:54 UTC (releng/9.3, 9.3-RELEASE-p10) 2015-02-18 22:29:52 UTC (stable/8, 8.4-STABLE) 2015-02-25 05:56:54 UTC (releng/8.4, 8.4-RELEASE-p24) CVE Name: CVE-2015-1349 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/>. I. Background BIND 9 is an implementation of the Domain Name System (DNS) protocols. The named(8) daemon is an Internet Domain Name Server. II. Problem Description BIND servers which are configured to perform DNSSEC validation and which are using managed keys (which occurs implicitly when using "dnssec-validation auto;" or "dnssec-lookaside auto;") may exhibit unpredictable behavior due to the use of an improperly initialized variable. III. Impact A remote attacker can trigger a crash of a name server that is configured to use managed keys under specific and limited circumstances. However, the complexity of the attack is very high unless the attacker has a specific network relationship to the BIND server which is targeted. IV. Workaround Only systems that runs BIND, including recursive resolvers and authoritative servers that performs DNSSEC validation and using managed-keys are affected. This issue can be worked around by not using "auto" for the dnssec-validation or dnssec-lookaside options and do not configure a managed-keys statement. Note that in order to do DNSSEC validation with this workaround one would have to configure an explicit trusted-keys statement with the appropriate keys. 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-15:05/bind.patch # fetch https://security.FreeBSD.org/patches/SA-15:05/bind.patch.asc # gpg --verify bind.patch.asc b) Apply the patch. Execute the following commands as root: # cd /usr/src # patch < /path/to/patch c) Recompile the operating system using buildworld and installworld as described in <URL:https://www.FreeBSD.org/handbook/makeworld.html>. Restart the applicable daemons, or reboot the system. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/8/ r278973 releng/8.4/ r279265 stable/9/ r278972 releng/9.3/ r279265 - ------------------------------------------------------------------------- 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://kb.isc.org/article/AA-01235> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1349> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-15:05.bind.asc> -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.1.1 (FreeBSD) iQIcBAEBCgAGBQJU7WjDAAoJEO1n7NZdz2rnKkgP/3vUBO8o5ofQFMUYSS1siPxZ 63OeeRlMabEgiWZaQ+V2O7/CPrHDIgJHQABx9kNoiutWD9TC3c5f7Yh4nfaXmbKe Ncu3EjF1Zw/uGbu3cXjboX0CYnBDYrPNJnzIvSG0UlTY5hEIi3FgN4v2Q3gzuU/2 3aUlFHyZb4GVzK+lA+wD0unOc6+il6LHPpSzwRbLpNxCB2J582HoCuw9i5NfMiOB KP8axZeNZLMpE90s3H/VD+7UIoe6eOC0kykH/DpuUIUxxlExK9c8f9QurpoCnOrV qwPAeWEYjmjZmMFivVZf5ugir6diaenfPjpXvUGNz2pCp5wlRkku71sMDsgnErX2 Fnuc6nCXqTb/XX6zQmz/236EEVr2UBuX0cXWT0Dvu8GznMij/s4J+9+/Pkjp/mr7 PfXj4H9UMv2Q3zOW7+Vb2Ru0zwfL9Dt90SyNbvt6DOA9KSNnUZIkN/pbKuS9fnHX Pw7eiNPs4Rq0Ui1DJDWVsJnZV2aVSw+qHxeMVtjCWbx3O7IVGgj5W7i95iAPHRJ4 PVd1oaI2WsteoLNGpfXUD5sQr9yFRU/mRKtgSjxtKRV/nIkdwfTNcHHXIl0XuIWw C7VmAjlZgqj7aacTZWiVXqiFkN6gDjjFv1lVYmuDQOiK52JCbcBavYnxzZxVzuSa yIpDuhJS5vIt/B5oepoZ =uquT -----END PGP SIGNATURE----- _______________________________________________ freebsd-announce@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-announce To unsubscribe, send any mail to "freebsd-announce-unsubscribe@freebsd.org"