libtiff: Array index error due improper handling of invalid ReferenceBlackWhite values

The TIFFYCbCrtoRGB function in LibTIFF 3.9.0 and 3.9.2, as used in ImageMagick, does not properly handle invalid ReferenceBlackWhite values, which allows remote attackers to cause a denial of service application crash via a crafted TIFF image that triggers an array index error, related to...