/usr/lib/x86_64-linux-gnu/libgloox.so is in libgloox-dev 1.0.18-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libgloox.so.15.0.0
/usr/lib/x86_64-linux-gnu/libgloox.so.15.0.0