diff --git a/wp-admin/includes/media.php b/wp-admin/includes/media.php
index 2977bdff13..54e2eb7e93 100644
--- a/wp-admin/includes/media.php
+++ b/wp-admin/includes/media.php
@@ -2423,7 +2423,7 @@ function edit_form_image_editor( $post ) {
 function attachment_submitbox_metadata() {
 	$post = get_post();
 
-	$filename = esc_html( basename( $post->guid ) );
+	$filename = esc_html( wp_basename( $post->guid ) );
 
 	$media_dims = '';
 	$meta = wp_get_attachment_metadata( $post->ID );
diff --git a/wp-includes/media.php b/wp-includes/media.php
index 48e1fb5f55..5b5501a158 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -1606,7 +1606,7 @@ function wp_prepare_attachment_for_js( $attachment ) {
 	$response = array(
 		'id'          => $attachment->ID,
 		'title'       => $attachment->post_title,
-		'filename'    => basename( $attachment->guid ),
+		'filename'    => wp_basename( $attachment->guid ),
 		'url'         => $attachment_url,
 		'link'        => get_attachment_link( $attachment->ID ),
 		'alt'         => get_post_meta( $attachment->ID, '_wp_attachment_image_alt', true ),