Because SharePoint servers are used for internal corporate collaboration, they make an ideal target for anyone trying to gain entry to sensitive information.
Today, Microsoft provided a short-term work-around that requires running a number of commands from the command prompt to shut down access to the at-risk part of the system. More detail on the work-around is available here.
On the company's Security, Research and Defense blog, they described the most likely way the vulnerability would be attacked:
Best advice: apply the workaround, and hope that Microsoft is able to provide a patch for this issue by within month's scheduled patch update, May 11.
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