/usr/lib/x86_64-linux-gnu/libsfml-network.so.2 is in libsfml-network2 2.1+dfsg2-1+b2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libsfml-network.so.2.1
/usr/lib/x86_64-linux-gnu/libsfml-network.so.2.1