diff --git a/apps/opencs/model/world/idtable.cpp b/apps/opencs/model/world/idtable.cpp
index 04aa271ccc..bde6412ece 100644
--- a/apps/opencs/model/world/idtable.cpp
+++ b/apps/opencs/model/world/idtable.cpp
@@ -84,6 +84,9 @@ bool CSMWorld::IdTable::setData (const QModelIndex &index, const QVariant &value
 
 Qt::ItemFlags CSMWorld::IdTable::flags (const QModelIndex & index) const
 {
+    if (!index.isValid())
+        return 0;
+
     Qt::ItemFlags flags = Qt::ItemIsSelectable | Qt::ItemIsEnabled;
 
     if (mIdCollection->getColumn (index.column()).isUserEditable())