The Netlink implementation in the Linux kernel before 3.2.30 does not properly handle messages that lack SCM_CREDENTIALS data, which might allow local users to spoof Netlink communication via a crafted message, as demonstrated by a message to (1) Avahi or (2) NetworkManager.
git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=e0e3cea46d31d23dc40df0a49a7a2c04fe8edfea
lists.opensuse.org/opensuse-security-announce/2012-10/msg00005.html
lists.opensuse.org/opensuse-updates/2013-02/msg00018.html
secunia.com/advisories/50848
www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.2.30
www.openwall.com/lists/oss-security/2012/08/22/1
www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
www.securityfocus.com/bid/55152
www.ubuntu.com/usn/USN-1599-1
www.ubuntu.com/usn/USN-1610-1
bugzilla.redhat.com/show_bug.cgi?id=850449
github.com/torvalds/linux/commit/e0e3cea46d31d23dc40df0a49a7a2c04fe8edfea