net/xfrm/xfrm_user.c in the Linux kernel before 3.6 does not verify that the actual Netlink message length is consistent with a certain header field, which allows local users to obtain sensitive information from kernel heap memory by leveraging the CAP_NET_ADMIN capability and providing a (1) new or (2) updated state.
https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.6.bz2
https://github.com/torvalds/linux/commit/ecd7918745234e423dd87fcc0c077da557909720