This indicates an attempt to access Microsoft Sharepoint calendar from within the network. The Microsoft SharePoint product is commecial CMS, which include wiki blog and many application site template. It does not contain any exploit.
Risk
Medium
Popularity
High
Characteristic
Loss of productivity? Have disclosed vulnerability? Can bypass firewall policy? Contain built-in function for other purposes? Can communicate in clear text or via proxy? Can support file transfer? Can be misused? Can tunnel other apps?