Microsoft released an update yesterday (9/26/2006) that addressed a known vulnerabiltiy with Internet Explorer. The vulnerability could potentially allow malicious code to be executed on a users computer, just by visiting an infected web site with Internet Explorer. For more details, please see ZDNet or Microsoft sites.
Gustavus users will be prompted to install the updates from the Updates Notification icon in the Task Menu (yellow shield in lower right hand corner). Users can also apply updates by visiting Microsoft Updates (must be done using Internet Explorer). Please apply all requested/critical updates. Mulitple reboots maybe required.