Multiple cross-site request forgery (CSRF) vulnerabilities in ZTE ZXDSL 831CII allow remote attackers to hijack the authentication of administrators for requests that (1) change the admin user name or (2) conduct cross-site scripting (XSS) attacks via the sysUserName parameter in a save action to adminpasswd.cgi or (3) change the admin user password via the sysPassword parameter in a save action to adminpasswd.cgi.