sudoedit (aka sudo -e) in sudo 1.6.8 opens a temporary file with root privileges, which allows local users to read arbitrary files via a symlink attack on the temporary file before quitting sudoedit.
https://exchange.xforce.ibmcloud.com/vulnerabilities/17424
http://www.sudo.ws/sudo/alerts/sudoedit.html
http://www.kb.cert.org/vuls/id/424358
http://www.ciac.org/ciac/bulletins/o-219.shtml
http://secunia.com/advisories/12596