Be aware administrators:
This fault is not caused by i-MSCP, but it's just a warning to check your systems for "possible" breaches.
Edit: A few things you can do, to prevent people from easily finding your Apache version is to modify your security configuration for apache.
& Restart Apache. /etc/init.d/apache2 restart
This will make it harder to find and exploit your installation if Debian/Ubuntu is affected by this.