diff --git a/wp-includes/class-wp-xmlrpc-server.php b/wp-includes/class-wp-xmlrpc-server.php
index a41810305d..ae9a658718 100644
--- a/wp-includes/class-wp-xmlrpc-server.php
+++ b/wp-includes/class-wp-xmlrpc-server.php
@@ -1067,6 +1067,7 @@ class wp_xmlrpc_server extends IXR_Server {
 			'description'      => $media_item->post_content,
 			'metadata'         => wp_get_attachment_metadata( $media_item->ID ),
 			'type'             => $media_item->post_mime_type,
+			'alt'              => get_post_meta( $media_item->ID, '_wp_attachment_image_alt', true ),
 		);
 
 		$thumbnail_src = image_downsize( $media_item->ID, $thumbnail_size );
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 41494f00b3..eb63da46cd 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.4-alpha-56636';
+$wp_version = '6.4-alpha-56637';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.