/usr/share/java/lttng-ust-agent-common.jar is in liblttng-ust-agent-java 2.9.0-2+deb9u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/java/lttng-ust-agent-common-2.9.0.jar
/usr/share/java/lttng-ust-agent-common-2.9.0.jar