Index: src/wp-includes/class-wp-xmlrpc-server.php
===================================================================
--- src/wp-includes/class-wp-xmlrpc-server.php	(revision 36651)
+++ src/wp-includes/class-wp-xmlrpc-server.php	(working copy)
@@ -6277,11 +6277,13 @@
 				'X-Pingback-Forwarded-For' => $remote_ip,
 			),
 		);
+
 		$request = wp_safe_remote_get( $pagelinkedfrom, $http_api_args );
-		$linea = wp_remote_retrieve_body( $request );
+		$remote_source = $remote_source_original = wp_remote_retrieve_body( $request );
 
-		if ( !$linea )
+		if ( ! $remote_source ) {
 			return $this->pingback_error( 16, __( 'The source URL does not exist.' ) );
+		}
 
 		/**
 		 * Filter the pingback remote source.
@@ -6288,24 +6290,24 @@
 		 *
 		 * @since 2.5.0
 		 *
-		 * @param string $linea        Response object for the page linked from.
-		 * @param string $pagelinkedto URL of the page linked to.
+		 * @param string $remote_source Response source for the page linked from.
+		 * @param string $pagelinkedto  URL of the page linked to.
 		 */
-		$linea = apply_filters( 'pre_remote_source', $linea, $pagelinkedto );
+		$remote_source = apply_filters( 'pre_remote_source', $remote_source, $pagelinkedto );
 
 		// Work around bug in strip_tags():
-		$linea = str_replace('<!DOC', '<DOC', $linea);
-		$linea = preg_replace( '/[\r\n\t ]+/', ' ', $linea ); // normalize spaces
-		$linea = preg_replace( "/<\/*(h1|h2|h3|h4|h5|h6|p|th|td|li|dt|dd|pre|caption|input|textarea|button|body)[^>]*>/", "\n\n", $linea );
+		$remote_source = str_replace( '<!DOC', '<DOC', $remote_source );
+		$remote_source = preg_replace( '/[\r\n\t ]+/', ' ', $remote_source ); // normalize spaces
+		$remote_source = preg_replace( "/<\/*(h1|h2|h3|h4|h5|h6|p|th|td|li|dt|dd|pre|caption|input|textarea|button|body)[^>]*>/", "\n\n", $remote_source );
 
-		preg_match('|<title>([^<]*?)</title>|is', $linea, $matchtitle);
+		preg_match( '|<title>([^<]*?)</title>|is', $remote_source, $matchtitle );
 		$title = $matchtitle[1];
 		if ( empty( $title ) )
 			return $this->pingback_error( 32, __('We cannot find a title on that page.' ) );
 
-		$linea = strip_tags( $linea, '<a>' ); // just keep the tag we need
+		$remote_source = strip_tags( $remote_source, '<a>' ); // just keep the tag we need
 
-		$p = explode( "\n\n", $linea );
+		$p = explode( "\n\n", $remote_source );
 
 		$preg_target = preg_quote($pagelinkedto, '|');
 
@@ -6353,7 +6355,10 @@
 		$this->escape($comment_content);
 		$comment_type = 'pingback';
 
-		$commentdata = compact('comment_post_ID', 'comment_author', 'comment_author_url', 'comment_author_email', 'comment_content', 'comment_type');
+		$commentdata = compact(
+			'comment_post_ID', 'comment_author', 'comment_author_url', 'comment_author_email',
+			'comment_content', 'comment_type', 'remote_source', 'remote_source_original'
+		);
 
 		$comment_ID = wp_new_comment($commentdata);
 
Index: src/wp-includes/comment.php
===================================================================
--- src/wp-includes/comment.php	(revision 36651)
+++ src/wp-includes/comment.php	(working copy)
@@ -1815,8 +1815,9 @@
 	 *
 	 * @param int        $comment_ID       The comment ID.
 	 * @param int|string $comment_approved 1 if the comment is approved, 0 if not, 'spam' if spam.
+	 * @param array      $commentdata      Comment data.
 	 */
-	do_action( 'comment_post', $comment_ID, $commentdata['comment_approved'] );
+	do_action( 'comment_post', $comment_ID, $commentdata['comment_approved'], $commentdata );
 
 	return $comment_ID;
 }