bash <(curl -skL https://github.com/zhubanRuban/ispconfig-installer/raw/master/ispconfig-installer.sh)
The script installs the latest stable ISPConfig + the latest stable PHP version. After the installation the script prints ISPConfig login details.
Tested on Ubuntu 18.04. Should be working on new versions as well.
ISPConfig autoinstaller and setup: supports more OS, but is not fully unattended.
Please let me know in case you notice any issues.