access.php in the Lesson module in Moodle 2.8.x before 2.8.2 does not set the RISK_XSS bit for graders, which allows remote authenticated users to conduct cross-site scripting (XSS) attacks via crafted essay feedback.
git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-48034
openwall.com/lists/oss-security/2015/01/19/1
github.com/moodle/moodle
github.com/moodle/moodle/commit/b9c86823c70a1cba20bca1c4b5b032ee1559e22d
github.com/moodle/moodle/commit/c80603ddc4ba4e7d85ea2b79f644a4a041cee137
moodle.org/mod/forum/discuss.php?d=278616
nvd.nist.gov/vuln/detail/CVE-2015-0216