In GraphicsMagick 1.4 snapshot-20171217 Q8, there is a heap-based buffer over-read in ReadMNGImage in coders/png.c, related to accessing one byte before testing whether a limit has been reached.

In GraphicsMagick 1.4 snapshot-20171217 Q8, there is a stack-based buffer over-read in WriteWEBPImage in coders/webp.c, related to an incompatibility with libwebp versions, 0.5.0 and later, that use a different structure type.

In GraphicsMagick 1.4 snapshot-20171217 Q8, there is a heap-based buffer over-read in ReadNewsProfile in coders/tiff.c, in which LocaleNCompare reads heap data beyond the allocated region.

LibTIFF before 4.0.6 mishandles the reading of TIFF files, as demonstrated by a heap-based buffer over-read in the ReadTIFFImage function in coders/tiff.c in GraphicsMagick 1.3.27.

In GraphicsMagick 1.3.27, there is an infinite loop and application hang in the ReadBMPImage function (coders/bmp.c). Remote attackers could leverage this vulnerability to cause a denial of service via an image file with a crafted bit-field mask value.