/usr/lib/x86_64-linux-gnu/libavutil.so.52 is in libavutil52 6:9.11-2ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libavutil.so.52.3.0
/usr/lib/x86_64-linux-gnu/libavutil.so.52.3.0