解决Discuz出现”您当前的访问请求当中含有非法字符，已经被系统拒绝“的问题。

编辑查找到以下代码

private function _xss_check() {
    static $check = array('"', '>', '<', '\'', '(', ')', 'CONTENT-TRANSFER-ENCODING');
    if(isset($_GET['formhash']) && $_GET['formhash'] !== formhash()) {
      system_error('request_tainting');
    }
    if($_SERVER['REQUEST_METHOD'] == 'GET' ) {
      $temp = $_SERVER['REQUEST_URI'];
    } elseif(empty ($_GET['formhash'])) {
      $temp = $_SERVER['REQUEST_URI'].file_get_contents('php://input');
    } else {
      $temp = '';
    }
    if(!empty($temp)) {
      $temp = strtoupper(urldecode(urldecode($temp)));
      foreach ($check as $str) {
        if(strpos($temp, $str) !== false) {
          system_error('request_tainting');
        }
      }
    }
    return true;
  }

更换以下:

rivate function _xss_check() {
    $temp = strtoupper(urldecode(urldecode($_SERVER['REQUEST_URI'])));
    if(strpos($temp, '<') !== false || strpos($temp, '"') !== false || strpos($temp, 'CONTENT-TRANSFER-ENCODING') !== false) {
      system_error('request_tainting');
    }
    return true;
  }

就可以解决了