WP User Avatar Plugin for WordPress contains a flaw that allows a cross-site scripting (XSS) attack. This flaw exists because the add_query_arg(), esc_url(), and esc_url_raw() functions do not validate input before returning it to users. This may allow a remote attacker to create a specially crafted request that would execute arbitrary script code in a user’s browser session within the trust relationship between their browser and the server.