Microsoft Exchange Outlook Web Access (OWA) in Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 20, Microsoft Exchange Server 2013 Cumulative Update 18, Microsoft Exchange Server 2013 Cumulative Update 19, Microsoft Exchange Server 2013 Service Pack 1, Microsoft Exchange Server 2016 Cumulative Update 7, and Microsoft Exchange Server 2016 Cumulative Update 8 allows an elevation of privilege vulnerability due to how links in the body of an email message are rewritten, aka "Microsoft Exchange Elevation of Privilege Vulnerability".