Multiple cross-site scripting (XSS) vulnerabilities in Microcart 1.0 allow remote attackers to inject arbitrary web script or HTML via the (1) PATH_INFO or (2) query string to _admin/index.php or (3) first_name, (4) last_name, (5) cc, (6) exp, (7) cvv, (8) address1, (9) address2, (10) city, (11) state, (12) zip, (13) phone, or (14) email parameter to checkout.php, which is not properly handled in an error message.