Sudo 1.6.9 before 1.8.5, when env_reset is disabled, does not properly check environment variables for the env_delete restriction, which allows local users with sudo permissions to bypass intended command restrictions via a crafted environment variable.
https://support.apple.com/kb/HT205031
http://www.ubuntu.com/usn/USN-2146-1
http://www.sudo.ws/sudo/alerts/env_add.html
http://www.securityfocus.com/bid/65997
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
http://www.openwall.com/lists/oss-security/2014/03/06/2
http://rhn.redhat.com/errata/RHSA-2014-0266.html
http://lists.opensuse.org/opensuse-security-announce/2014-04/msg00003.html
http://lists.apple.com/archives/security-announce/2015/Aug/msg00001.html