/usr/lib/jvm/java-8-openjdk-amd64/bin/itweb-settings is in icedtea-netx 1.6.2-3.1ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/jvm/java-8-openjdk-amd64/bin/../jre/bin/itweb-settings