/lib/x86_64-linux-gnu/libntfs-3g.so.831 is in ntfs-3g 1:2012.1.15AR.1-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /lib/x86_64-linux-gnu/libntfs-3g.so.831.0.0
/lib/x86_64-linux-gnu/libntfs-3g.so.831.0.0