An elevation of privilege vulnerability exists in the Windows redirected drive buffering system (rdbss.sys) when the operating system improperly handles specific local calls within Windows 7 for 32-bit systems. When this vulnerability is exploited within other versions of Windows it can cause a denial of service, but not an elevation of privilege.To exploit this vulnerability, a low-level authenticated attacker could run a specially crafted application.The security update addresses the vulnerability by correcting how rdbss.sys handles these local calls.