Why not try another freeware anti virus program to see if it is Avast or not. You can always go back to Avast if there is no change.
I haven't seen any more warnings since I removed Avast and installed Bullguard.
Some anti virus programs have a built in firewall that will allow certain things in or block them depending on whether they think they are malicious or not. Avast may think or know that this particular script is not malicious but is just warning you of its presence. Wait to see if the techy guys come up with anything.