/usr/lib/x86_64-linux-gnu/libtiff.so is in libtiff4-dev 3.9.5-2ubuntu1.9.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libtiff.so.4.3.4
/usr/lib/x86_64-linux-gnu/libtiff.so.4.3.4