Microsoft Client Server Run-time Subsystem is a client/server run-time subsystem from Microsoft Corporation of the United States, manifested as the csrss.exe process. It is a component of the Windows NT operating system family, appearing in Windows NT 3.1 and later systems, and provides the user mode side of the Win32 subsystem.An elevation of privilege vulnerability exists in the Microsoft Client Server Run-time Subsystem (CSRSS), which stems from the existence of improper application An attacker could exploit the vulnerability to cause an elevation of privilege.