diff --git wp-includes/functions.php wp-includes/functions.php
index d13a5b1..a19a567 100644
--- wp-includes/functions.php
+++ wp-includes/functions.php
@@ -2048,6 +2048,8 @@ function wp_ext2type( $ext ) {
  * @return array Values with extension first and mime type.
  */
 function wp_check_filetype( $filename, $mimes = null ) {
+	$filename = parse_url( $filename, PHP_URL_PATH );
+
 	if ( empty($mimes) )
 		$mimes = get_allowed_mime_types();
 	$type = false;