diff --git a/src/devices/wwan/nm-modem.c b/src/devices/wwan/nm-modem.c
index 10baa424af..a1089e3b83 100644
--- a/src/devices/wwan/nm-modem.c
+++ b/src/devices/wwan/nm-modem.c
@@ -1665,6 +1665,7 @@ finalize (GObject *object)
 	g_free (priv->driver);
 	g_free (priv->control_port);
 	g_free (priv->data_port);
+	g_free (priv->ppp_iface);
 	g_free (priv->device_id);
 	g_free (priv->sim_id);
 	g_free (priv->sim_operator_id);