diff --git a/wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php b/wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php
index 1d78928fc4..91b21587b1 100644
--- a/wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php
+++ b/wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php
@@ -141,6 +141,8 @@ class WP_REST_Attachments_Controller extends WP_REST_Posts_Controller {
 			return $insert;
 		}
 
+		$schema = $this->get_item_schema();
+
 		// Extract by name.
 		$attachment_id = $insert['attachment_id'];
 		$file          = $insert['file'];
@@ -149,6 +151,14 @@ class WP_REST_Attachments_Controller extends WP_REST_Posts_Controller {
 			update_post_meta( $attachment_id, '_wp_attachment_image_alt', sanitize_text_field( $request['alt_text'] ) );
 		}
 
+		if ( ! empty( $schema['properties']['meta'] ) && isset( $request['meta'] ) ) {
+			$meta_update = $this->meta->update_value( $request['meta'], $attachment_id );
+
+			if ( is_wp_error( $meta_update ) ) {
+				return $meta_update;
+			}
+		}
+
 		$attachment    = get_post( $attachment_id );
 		$fields_update = $this->update_additional_fields_for_object( $attachment, $request );
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 4e95425bd5..87e861ea90 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4-alpha-47260';
+$wp_version = '5.4-alpha-47261';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.