diff --git a/lib/wp/spa-json.c b/lib/wp/spa-json.c
index 56e625ee..4bcfb231 100644
--- a/lib/wp/spa-json.c
+++ b/lib/wp/spa-json.c
@@ -822,7 +822,8 @@ wp_spa_json_object_get_valist (WpSpaJson *self, va_list args)
     g_return_val_if_fail (key_str, FALSE);
 
     g_value_unset (&item);
-    wp_iterator_next (it, &item);
+    if (!wp_iterator_next (it, &item))
+      return FALSE;
     value = g_value_get_boxed (&item);
 
     if (g_strcmp0 (key_str, lookup_key) == 0) {
diff --git a/modules/module-lua-scripting/json.c b/modules/module-lua-scripting/json.c
index 78534e24..3ad1435d 100644
--- a/modules/module-lua-scripting/json.c
+++ b/modules/module-lua-scripting/json.c
@@ -145,7 +145,8 @@ push_luajson (lua_State *L, WpSpaJson *json)
       key_str = wp_spa_json_parse_string (key);
       g_warn_if_fail (key_str);
       g_value_unset (&item);
-      wp_iterator_next (it, &item);
+      if (!wp_iterator_next (it, &item))
+        break;
       value = g_value_get_boxed (&item);
       push_luajson (L, value);
       lua_setfield (L, -2, key_str);