Cross-site scripting (XSS) vulnerability in mod/quiz/report/statistics/statistics_question_table.php in Moodle through 2.5.9, 2.6.x before 2.6.9, 2.7.x before 2.7.6, and 2.8.x before 2.8.4 allows remote authenticated users to inject arbitrary web script or HTML by leveraging the student role for a crafted quiz response.
https://github.com/advisories/GHSA-w77v-xpxr-c6pv
https://moodle.org/mod/forum/discuss.php?d=307387
http://openwall.com/lists/oss-security/2015/03/16/1
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-49364