File GraphicsMagick-CVE-2017-16546.patch of Package GraphicsMagick.7727

Index: GraphicsMagick-1.3.25/coders/wpg.c
===================================================================
--- GraphicsMagick-1.3.25.orig/coders/wpg.c	2017-11-21 17:06:50.050119234 +0100
+++ GraphicsMagick-1.3.25/coders/wpg.c	2017-11-21 17:06:42.217987185 +0100
@@ -1030,6 +1030,9 @@ static Image *ReadWPGImage(const ImageIn
               WPG_Palette.StartIndex=ReadBlobLSBShort(image);
               WPG_Palette.NumOfEntries=ReadBlobLSBShort(image);
 
+              if (WPG_Palette.StartIndex > WPG_Palette.NumOfEntries)
+                ThrowReaderException(CorruptImageError,InvalidColormapIndex,image);
+
               image->colors=WPG_Palette.NumOfEntries;
               if (!AllocateImageColormap(image,image->colors))
                 goto NoMemory;