A reflected cross-site scripting vulnerability was discovered in Moodle. This flaw exists due to insufficient sanitization of user-supplied data in policy tool. An attacker can trick the victim to open a specially crafted link that executes an arbitrary HTML and script code in user's browser in context of vulnerable website. This vulnerability may allow an attacker to perform cross-site scripting (XSS) attacks to gain access potentially sensitive information and modification of web pages.