[Zope] Does ZWiki compromise Win2003 security behind a firewall?

Yes or no. OK, I know it's not that simple. I am working in an agency that employs a third party to manage our network. The third party is reluctant to install Zope and ZWiki for me, claiming that this will open "the system" to "potential attacks". The wiki would be for use by agency personnel only and be available on a non-routable address, behind a firewall. Could someone tell me how this could be a security risk? Thanks for any ideas. Bill