The rtnl_fill_ifinfo function in net/core/rtnetlink.c in the Linux kernel before 3.8.4 does not initialize a certain structure member, which allows local users to obtain sensitive information from kernel stack memory via a crafted application.
https://github.com/torvalds/linux/commit/84d73cd3fb142bf1298a8c13fd4ca50fd2432372
https://bugzilla.redhat.com/show_bug.cgi?id=923652
http://www.ubuntu.com/usn/USN-1814-1
http://www.ubuntu.com/usn/USN-1813-1
http://www.ubuntu.com/usn/USN-1812-1
http://www.ubuntu.com/usn/USN-1811-1
http://www.ubuntu.com/usn/USN-1809-1
http://www.openwall.com/lists/oss-security/2013/03/20/1
http://www.mandriva.com/security/advisories?name=MDVSA-2013:176
http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.8.4
http://rhn.redhat.com/errata/RHSA-2013-1051.html
http://lists.opensuse.org/opensuse-updates/2013-12/msg00129.html
http://lists.opensuse.org/opensuse-security-announce/2013-07/msg00018.html