/usr/lib/x86_64-linux-gnu/libradcli.so is in libradcli-dev 1.2.6-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libradcli.so.4.1.2
/usr/lib/x86_64-linux-gnu/libradcli.so.4.1.2