Verifying From header before send mail

Signed-off-by: Michael Granados <michaelgranados@gmail.com>
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index a55d2ff..34ce5b1 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -1630,6 +1630,12 @@
 	 */
 	public function send($auto_clear = TRUE)
 	{
+		if ( ! isset($this->_headers['From']) )
+		{
+			$this->_set_error_message('lang:email_no_sender');
+			return FALSE;
+		}
+
 		if ($this->_replyto_flag === FALSE)
 		{
 			$this->reply_to($this->_headers['From']);