The copy_to_user_auth function in net/xfrm/xfrm_user.c in the Linux kernel before 3.6 uses an incorrect C library function for copying a string, which allows local users to obtain sensitive information from kernel heap memory by leveraging the CAP_NET_ADMIN capability.
https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.6.bz2
https://github.com/torvalds/linux/commit/4c87308bdea31a7b4828a51f6156e6f721a1fcc9
http://www.openwall.com/lists/oss-security/2013/03/05/13