/usr/lib/x86_64-linux-gnu/libcidr.so is in libcidr-dev 1.2.3-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libcidr.so.0
/usr/lib/x86_64-linux-gnu/libcidr.so.0