diff --git a/app/paint/gimpbrushcore.c b/app/paint/gimpbrushcore.c
index b5b41657b1..0492ba0033 100644
--- a/app/paint/gimpbrushcore.c
+++ b/app/paint/gimpbrushcore.c
@@ -999,6 +999,8 @@ gimp_brush_core_replace_canvas (GimpBrushCore            *core,
                                brush_opacity,
                                image_opacity,
                                mode);
+
+      g_object_unref (paint_mask);
     }
 }