diff --git a/apps/files/ajax/list.php b/apps/files/ajax/list.php
index 12c2d99338d1..68bfc0b4f0ca 100644
--- a/apps/files/ajax/list.php
+++ b/apps/files/ajax/list.php
@@ -131,6 +131,14 @@
 			'message' => $l->t('Storage invalid')
 		)
 	));
+} catch (\OCP\Files\NotPermittedException $e) {
+	\OCP\Util::logException('files', $e);
+	OCP\JSON::error(array(
+		'data' => array(
+			'exception' => '\OCP\Files\NotPermittedException',
+			'message' => $l->t('Permission denied accessing the resource or temporary storage error')
+		)
+	));
 } catch (\Exception $e) {
 	\OCP\Util::logException('files', $e);
 	OCP\JSON::error(array(
diff --git a/lib/private/files/objectstore/eosutil.php b/lib/private/files/objectstore/eosutil.php
index 182e0d07b3d0..98da18e2f94c 100644
--- a/lib/private/files/objectstore/eosutil.php
+++ b/lib/private/files/objectstore/eosutil.php
@@ -1058,7 +1058,8 @@ public static function getFolderContents($eosPath, $additionalParameterCallback
 		$files = array();
 		list($result, $errcode) = EosCmd::exec($getFolderContents);
 		if ($errcode !== 0) {
-			return $files;
+			// Safe bet: always throw permission denied if the call to eos fails.
+			throw new \OCP\Files\NotPermittedException("cannot list contents of eos folder");
 		}
 
 		// we need to obtain the tree size performing an 'ls' command and merging attributes