  private function catchWarning ($errno, $errstr, $errfile, $errline) {
    $this->error[] = array(
      'error' => "Connecting to the POP3 server raised a PHP warning: ",
      'errno' => $errno,
      'errstr' => $errstr
    );
  }
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.