/usr/lib/x86_64-linux-gnu/libaff4.so is in libaff4-dev 0.24.post1-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libaff4.so.0.0.0
/usr/lib/x86_64-linux-gnu/libaff4.so.0.0.0