/usr/i686-linux-gnu/libx32/libubsan.so.0 is in libx32ubsan0-i386-cross 7.3.0-16ubuntu3cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/i686-linux-gnu/libx32/libubsan.so.0.0.0
/usr/i686-linux-gnu/libx32/libubsan.so.0.0.0