Technical Information

Brief overview of the risk:
The most severe vulnerabilities are in Microsoft Exchange Server WebReady Document Viewing and could allow remote code execution in the security context of the transcoding service on the Exchange server if a user previews a specially crafted file using Outlook Web App (OWA). The transcoding service in Exchange that is used for WebReady Document Viewing is running in the LocalService account. The LocalService account has minimum privileges on the local computer and presents anonymous credentials on the network.
Detailed Information on the risk:

A denial of service vulnerability exists in Microsoft Exchange Server when Exchange improperly handles RSS feeds. The vulnerability could cause the Information Store service on the affected system to become unresponsive until the process is forcibly terminated. This unresponsive condition could cause Exchange databases to dismount, and potentially lead to corruption of databases, affecting user mailboxes.

Further information on this exploit is available at : MS12-080