The "internal state tracking" code for the random and urandom devices in FreeBSD 5.5, 6.1 through 6.3, and 7.0 beta 4 allows local users to obtain portions of previously-accessed random values, which could be leveraged to bypass protection mechanisms that rely on secrecy of those values.
https://exchange.xforce.ibmcloud.com/vulnerabilities/38764
http://www.vupen.com/english/advisories/2007/4053
http://www.securitytracker.com/id?1019022
http://www.securityfocus.com/bid/26642
http://security.FreeBSD.org/advisories/FreeBSD-SA-07:09.random.asc