/usr/lib/x86_64-linux-gnu/libroken.so.18 is in libroken18-heimdal 1.7~git20150920+dfsg-4ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libroken.so.18.1.0
/usr/lib/x86_64-linux-gnu/libroken.so.18.1.0