/usr/lib/x86_64-linux-gnu/libkeyutils.so is in libkeyutils-dev 1.5.9-9.2ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /lib/x86_64-linux-gnu/libkeyutils.so.1
/lib/x86_64-linux-gnu/libkeyutils.so.1