The ReadTIFFImage function in coders/tiff.c in ImageMagick 7.0.7-23 Q16 does not properly validate the amount of image data in a file, which allows remote attackers to cause a denial of service (memory allocation failure in the AcquireMagickMemory function in MagickCore/memory.c).
The TIFFSetProfiles function in coders/tiff.c in ImageMagick 7.0.6 has incorrect expectations about whether LibTIFF TIFFGetField return values imply that data validation has occurred, which allows remote attackers to cause a denial of service (use-after-free after an invalid call to TIFFSetField, and application crash) via a crafted file.