/usr/lib/x86_64-linux-gnu/librbio.so.2 is in librbio2 1:5.1.2-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/librbio.so.2.2.6
/usr/lib/x86_64-linux-gnu/librbio.so.2.2.6