Multiple cross-site scripting (XSS) vulnerabilities in Moodle 1.8.x before 1.8.12 and 1.9.x before 1.9.8 allow remote attackers to inject arbitrary web script or HTML via vectors related to (1) the Login-As feature or (2) when the global search feature is enabled, unspecified global search forms in the Global Search Engine. NOTE: vector 1 might be resultant from a cross-site request forgery (CSRF) vulnerability.
http://www.vupen.com/english/advisories/2010/1107
http://lists.opensuse.org/opensuse-security-announce/2010-05/msg00001.html