/usr/lib/x86_64-linux-gnu/libserf-1.so.1 is in libserf-1-1 1.3.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libserf-1.so.1.3.0
/usr/lib/x86_64-linux-gnu/libserf-1.so.1.3.0