diff --git a/src/modules/sensors/sensors.cpp b/src/modules/sensors/sensors.cpp
index 5315c5e387..e260aae45c 100644
--- a/src/modules/sensors/sensors.cpp
+++ b/src/modules/sensors/sensors.cpp
@@ -655,7 +655,7 @@ Sensors::parameters_update()
 	}
 
 	if (param_get(_parameter_handles.rc_map_loiter_sw, &(_parameters.rc_map_loiter_sw)) != OK) {
-		warnx(paramerr);
+		warnx("%s", paramerr);
 	}
 
 	if (param_get(_parameter_handles.rc_map_flaps, &(_parameters.rc_map_flaps)) != OK) {