/usr/lib/camitk-3.3/components/libstl.so is in libcamitk3-dev 3.3.2-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/camitk-3.3/components/libstl.so.3
/usr/lib/camitk-3.3/components/libstl.so.3