/usr/include/osmium/util/ is in libosmium2-dev 2.11.4-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/osmium/util/cast.hpp
/usr/include/osmium/util/compatibility.hpp
/usr/include/osmium/util/config.hpp
/usr/include/osmium/util/delta.hpp
/usr/include/osmium/util/double.hpp
/usr/include/osmium/util/endian.hpp
/usr/include/osmium/util/file.hpp
/usr/include/osmium/util/iterator.hpp
/usr/include/osmium/util/memory.hpp
/usr/include/osmium/util/memory_mapping.hpp
/usr/include/osmium/util/minmax.hpp
/usr/include/osmium/util/misc.hpp
/usr/include/osmium/util/options.hpp
/usr/include/osmium/util/progress_bar.hpp
/usr/include/osmium/util/string.hpp
/usr/include/osmium/util/timer.hpp
/usr/include/osmium/util/verbose_output.hpp