Buffer overflow in the gethostbyname_r and other unspecified NSS functions in the GNU C Library (aka glibc or libc6) before 2.22 allows context-dependent attackers to cause a denial of service (crash) or execute arbitrary code via a crafted DNS response, which triggers a call with a misaligned buffer.
https://www.sourceware.org/ml/libc-alpha/2015-08/msg00609.html
https://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=2959eda9272a03386
https://sourceware.org/bugzilla/show_bug.cgi?id=18287
https://security.gentoo.org/glsa/201602-02
https://rhn.redhat.com/errata/RHSA-2015-0863.html
http://www.ubuntu.com/usn/USN-2985-2
http://www.ubuntu.com/usn/USN-2985-1
http://www.securitytracker.com/id/1032178
http://www.securityfocus.com/bid/74255
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
http://www.debian.org/security/2016/dsa-3480
http://lists.opensuse.org/opensuse-security-announce/2016-02/msg00036.html
http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00019.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177404.html