/usr/bin/debconf-apt-progress
/usr/bin/debconf-communicate
/usr/bin/debconf-copydb
/usr/bin/debconf
/usr/bin/debconf-escape
/usr/bin/debconf-set-selections
/usr/bin/debconf-show
/usr/sbin/dpkg-preconfigure
/usr/sbin/dpkg-reconfigure
You may install this package on Debian with
apt-get
install debconf