diff --git a/MagickWand/operation.c b/MagickWand/operation.c
index 70a1f5a..5488e8b 100644
--- a/MagickWand/operation.c
+++ b/MagickWand/operation.c
@@ -1986,7 +1986,7 @@
break;
/* Create a write mask from cli_wand mask image */
/* FUTURE: use Alpha operations instead and create a Grey Image */
- mask_view=AcquireCacheView(mask_image);
+ mask_view=AcquireAuthenticCacheView(mask_image,_exception);
for (y=0; y < (ssize_t) mask_image->rows; y++)
{
q=GetCacheViewAuthenticPixels(mask_view,0,y,mask_image->columns,1,