diff --git a/lib/Command/SharesFiles.php b/lib/Command/SharesFiles.php
index f83a27bad..6c0abaff1 100644
--- a/lib/Command/SharesFiles.php
+++ b/lib/Command/SharesFiles.php
@@ -218,7 +218,7 @@ private function displayShares(
 				$row = array_merge(
 					$row, [
 						$sharedTo . ' (' . $recipient->getSingleId() . ', '
-						. Circle::$DEF_SOURCE[$recipient->getBasedOn()->getSource()] . ')',
+						. (Circle::$DEF_SOURCE[$recipient?->getBasedOn()->getSource()] ?? 'undef') . ')',
 						(($share->getChildId() > 0) ? $share->getChildFileTarget(
 						) : $share->getFileTarget()),
 					]