/usr/lib/x86_64-linux-gnu/libOTBOSSIMAdapters-6.4.so is in libotb-dev 6.4.0+dfsg-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libOTBOSSIMAdapters-6.4.so.1
/usr/lib/x86_64-linux-gnu/libOTBOSSIMAdapters-6.4.so.1