Elevation of privilege vulnerabilities exist in Microsoft SQL Server when it improperly handles pointer casting. An attacker could exploit the vulnerabilities if their credentials allow access to an affected SQL server database. An attacker who successfully exploited the vulnerabilities could gain elevated privileges that could be used to view, change, or delete data; or create new accounts.
The security update addresses the vulnerabilities by correcting how SQL Server handles pointer casting

Further information on this exploit is available at : MS16-136