tools/tiffcp.c in LibTIFF 4.0.7 allows remote attackers to cause a denial of service (integer underflow and heap-based buffer under-read) or possibly have unspecified other impact via a crafted TIFF image, related to "READ of size 78490" and libtiff/tif_unix.c:115:23.
https://usn.ubuntu.com/3602-1/
https://security.gentoo.org/glsa/201709-27
https://github.com/vadz/libtiff/commit/5397a417e61258c69209904e652a1f409ec3b9df
https://blogs.gentoo.org/ago/2017/01/01/libtiff-multiple-heap-based-buffer-overflow/