The sco_sock_getsockopt_old function in net/bluetooth/sco.c in the Linux kernel before 2.6.39 does not initialize a certain structure, which allows local users to obtain potentially sensitive information from kernel stack memory via the SCO_CONNINFO option.
https://github.com/torvalds/linux/commit/c4c896e1471aec3b004a693c689f60be3b17ac86
https://bugzilla.redhat.com/show_bug.cgi?id=681259
http://www.openwall.com/lists/oss-security/2011/03/01/10
http://rhn.redhat.com/errata/RHSA-2012-1156.html
http://rhn.redhat.com/errata/RHSA-2011-0833.html
http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39