/usr/lib/x86_64-linux-gnu/librudecgi.so is in librudecgi-dev 5.0.0-1.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/librudecgi.so.5.0.0
/usr/lib/x86_64-linux-gnu/librudecgi.so.5.0.0