diff --git a/htdocs/comm/action/class/actioncomm.class.php b/htdocs/comm/action/class/actioncomm.class.php
index d198de99b1a..5eca0fd136f 100644
--- a/htdocs/comm/action/class/actioncomm.class.php
+++ b/htdocs/comm/action/class/actioncomm.class.php
@@ -1239,6 +1239,9 @@ class ActionComm extends CommonObject
 					if (!is_array($val)) {	// For backward compatibility when val=id
 						$val = array('id' => $val);
 					}
+					if (!isset($val['id']) || !is_scalar($val['id'])) {
+						continue;
+					}
 					if (!empty($already_inserted[$val['id']])) {
 						continue;
 					}