FreeBSD 8.4 before p14, 9.1 before p17, 9.2 before p10, and 10.0 before p7 does not properly initialize the buffer between the header and data of a control message, which allows local users to obtain sensitive information from kernel memory via unspecified vectors.
https://exchange.xforce.ibmcloud.com/vulnerabilities/94448
http://www.securitytracker.com/id/1030539
http://www.securityfocus.com/bid/68466
http://www.freebsd.org/security/advisories/FreeBSD-SA-14:17.kmem.asc