diff --git a/gdk/win32/gdkproperty-win32.c b/gdk/win32/gdkproperty-win32.c
index cc0bd25b7c..a2ef3bee45 100644
--- a/gdk/win32/gdkproperty-win32.c
+++ b/gdk/win32/gdkproperty-win32.c
@@ -186,6 +186,12 @@ _gdk_win32_window_change_property (GdkWindow    *window,
       format == 8 &&
       mode == GDK_PROP_MODE_REPLACE)
     {
+      if (type == _image_bmp && nelements < sizeof (BITMAPFILEHEADER))
+        {
+           g_warning ("Clipboard contains invalid bitmap data");
+           return;
+        }
+
       if (type == _utf8_string)
 	{
 	  if (!OpenClipboard (GDK_WINDOW_HWND (window)))
diff --git a/gdk/win32/gdkselection-win32.c b/gdk/win32/gdkselection-win32.c
index c2a0893645..8c54240782 100644
--- a/gdk/win32/gdkselection-win32.c
+++ b/gdk/win32/gdkselection-win32.c
@@ -1285,6 +1285,8 @@ _gdk_win32_selection_convert_to_dib (HGLOBAL  hdata,
 
   if (target == _image_bmp)
     {
+      g_return_val_if_fail (GlobalSize (hdata) >= sizeof (BITMAPFILEHEADER), NULL);
+
       /* No conversion is needed, just strip the BITMAPFILEHEADER */
       HGLOBAL hdatanew;
       SIZE_T size = GlobalSize (hdata) - sizeof (BITMAPFILEHEADER);