Moodle through 2.3.11, 2.4.x before 2.4.11, 2.5.x before 2.5.7, 2.6.x before 2.6.4, and 2.7.x before 2.7.1 does not enforce certain capability requirements in (1) notes/index.php and (2) user/edit.php, which allows remote attackers to obtain potentially sensitive username and course information via a modified URL.
https://moodle.org/mod/forum/discuss.php?d=264267
http://openwall.com/lists/oss-security/2014/07/21/1
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-45760