/usr/lib/x86_64-linux-gnu/libgnutls.so is in libgnutls28-dev 3.3.8-6+deb8u7.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libgnutls-deb0.so.28.41.0
/usr/lib/x86_64-linux-gnu/libgnutls-deb0.so.28.41.0