Multiple cross-site scripting (XSS) vulnerabilities in lib/weblib.php in Moodle 1.9.x before 1.9.12 allow remote attackers to inject arbitrary web script or HTML via vectors related to URL encoding.
http://openwall.com/lists/oss-security/2011/11/14/1
http://moodle.org/mod/forum/discuss.php?d=175592
http://git.moodle.org/gw?p=moodle.git%3Ba=commit%3Bh=5a3010310bff0b3946804a72ca2d6bc166a0028f