diff --git a/src/BaseModule.php b/src/BaseModule.php
index ce7774bfd0..a9f67f2375 100644
--- a/src/BaseModule.php
+++ b/src/BaseModule.php
@@ -140,6 +140,10 @@ abstract class BaseModule
 			return false;
 		}
 
+		if (empty($a->user)) {
+			return false;
+		}
+
 		$sec_hash = hash('whirlpool', $a->user['guid'] . $a->user['prvkey'] . session_id() . $x[0] . $typename);
 
 		return ($sec_hash == $x[1]);