FreeBSD Security Advisory FreeBSD-SA-16:37.libc
6 December, 2016 by email@example.com | freebsd
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-16:37.libc Security Advisory The FreeBSD Project Topic: link_ntoa(3) buffer overflow Category: core Module: libc Announced: 2016-12-06 Affects: All supported versions of FreeBSD. Corrected: 2016-12-06 18:53:21 UTC (stable/11, 11.0-STABLE) 2016-12-06 18:49:38 UTC (releng/11.0, 11.0-RELEASE-p4) 2016-12-06 18:53:46 UTC (stable/10, 10.3-STABLE) 2016-12-06 18:49:48 UTC (releng/10.3, 10.3-RELEASE-p13) 2016-12-06 18:49:54 UTC (releng/10.2, 10.2-RELEASE-p26) 2016-12-06 18:49:59 UTC (releng/10.1, 10.1-RELEASE-p43) 2016-12-06 18:54:04 UTC (stable/9, 9.3-STABLE) 2016-12-06 18:50:06 UTC (releng/9.3, 9.3-RELEASE-p51) CVE Name: CVE-2016-6559 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 The link_ntoa(3) function generates ASCII representation of a link-level address and is avaliable as part of standard C library (libc). II. Problem Description A specially crafted argument can trigger a static buffer overflow in the library, with possibility to rewrite following static buffers that belong to other library functions. III. Impact Due to very limited use of the function in the existing applications, and limited length of the overflow, exploitation of the vulnerability does not seem feasible. None of the utilities and daemons in the base system are known to be vulnerable. However, careful review of third party software that may use the function was not performed. 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 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 Restart all daemons that use the library, or reboot the system. 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-16:37/libc.patch # fetch https://security.FreeBSD.org/patches/SA-16:37/libc.patch.asc # gpg --verify libc.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 all daemons that use the library, or reboot the system. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/9/ r309646 releng/9.3/ r309637 stable/10/ r309645 releng/10.1/ r309636 releng/10.2/ r309635 releng/10.3/ r309634 stable/11/ r309644 releng/11.0/ r309633 - ------------------------------------------------------------------------- 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:http://www.kb.cert.org/vuls/id/548487> <URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-6559> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-16:37.libc.asc> -----BEGIN PGP SIGNATURE----- iQIcBAEBCgAGBQJYRw1vAAoJEO1n7NZdz2rnk5sP/18NuTRoit3jfa1uHCYMyTOB vOGtNtn5xs8NNY4wAdYx2cF3CscTZEWyQtXWsMWzXgbWI0KrWteacGDaDlFwraCu 9/TJmkCQC5FCfYsgQFOpOPtMl9W+gY2ZrmEPXsfc/smjvIas3fPCBjnoRM2qQlfc 25YIut+S6OFhm2XM42t/jljbLs6b/PJikeKt7kEEEjKKXWHNwLEYjbtEyelKxD1i 1IBVe4Run2RajERg99yCznAGGvRo2hbGmnV59kDAilanJK+s3pzCOBFdnKyZd/2l Ie8B/fKEXRJyFgJF7A9eSuElTV5fCFfX05AC3PXMoi+GsVPQqhEpNb1FvJoANiFL l61nbqkM5KEteIWvf1udHZo6kjhYY4YlvutXW7o41XaUhnaO3dC+4+VpfTycH/no j8kVFS1Y9oun31TTZ/+aQqnCfozAMKFaZtrZI3UkSR1kjz5Z5Rqrc4isBhXXP1dQ QC87THCyW2D1+E0LvMyJEWKtjGMd8OO5KZjvTxcmxDSrqEOn+yGT1Lp8G/NLuQ4D zcarPPl2eE0bikvL/T/k7OdpplTDXoaCOHiMIr02WpbJwipw6HD4FZrg1IQu/Db9 2cHihr/tS1mbr7k/VKUyIZvQQhZ9j72m4wwBk0CFEG8DeZtMeSum1xgLTEjUerHe rWrKG2feWv//R0BvVNhu =8y53 -----END PGP SIGNATURE----- _______________________________________________ firstname.lastname@example.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-announce To unsubscribe, send any mail to "email@example.com"