mod/lti/ajax.php in Moodle through 2.5.9, 2.6.x before 2.6.7, 2.7.x before 2.7.4, and 2.8.x before 2.8.2 does not consider the moodle/course:manageactivities and mod/lti:addinstance capabilities before proceeding with registered-tool list searches, which allows remote authenticated users to obtain sensitive information via requests to the LTI Ajax service.
https://moodle.org/mod/forum/discuss.php?d=278611
http://openwall.com/lists/oss-security/2015/01/19/1
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-47920