diff --git a/modules/image/image.test b/modules/image/image.test
index 1ca8465..f120156 100644
--- a/modules/image/image.test
+++ b/modules/image/image.test
@@ -218,6 +218,12 @@ class ImageStylesPathAndUrlTestCase extends DrupalWebTestCase {
       $this->drupalGet($generate_url);
       $this->assertResponse(200, t('Image was generated at the URL.'));
 
+      // Make sure that access is denied for existing style files if we do not
+      // have access.
+      variable_del('image_module_test_file_download');
+      $this->drupalGet($generate_url);
+      $this->assertResponse(403, 'Confirmed that access is denied for the private image style.');
+
       // Repeat this with a different file that we do not have access to and
       // make sure that access is denied.
       $file_noaccess = array_shift($files);