core/modules/file/src/FileFieldUploader.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/modules/file/src/FileFieldUploader.php b/core/modules/file/src/FileFieldUploader.php
index aca9705825..a76f3ac82e 100644
--- a/core/modules/file/src/FileFieldUploader.php
+++ b/core/modules/file/src/FileFieldUploader.php
@@ -253,7 +253,7 @@ public function validateAndParseContentDispositionHeader(Request $request) {
 
     // Make sure only the filename component is returned. Path information is
     // stripped as per https://tools.ietf.org/html/rfc6266#section-4.3.
-    return basename($filename);
+    return $this->fileSystem->basename($filename);
   }
 
   /**