NtOpenProcessTokenEx function

The ZwOpenProcessTokenEx routine opens the access token associated with a process.


__kernel_entry NTSYSCALLAPI NTSTATUS NtOpenProcessTokenEx(
  HANDLE      ProcessHandle,
  ACCESS_MASK DesiredAccess,
  ULONG       HandleAttributes,
  PHANDLE     TokenHandle



Handle to the process whose access token is to be opened. The handle must have PROCESS_QUERY_INFORMATION access. Use the NtCurrentProcess macro, defined in Ntddk.h, to specify the current process.


ACCESS_MASK structure specifying the requested types of access to the access token. These requested access types are compared with the token's discretionary access-control list (DACL) to determine which accesses are granted or denied.


Attributes for the access token handle. Only OBJ_KERNEL_HANDLE is currently supported. If the caller is not running in the system process context, it must specify OBJ_KERNEL_HANDLE for this parameter.


Pointer to a caller-allocated variable that receives a handle to the newly opened access token.

Return Value

ZwOpenProcessTokenEx returns STATUS_SUCCESS or an appropriate error status. Possible error status codes include the following:

Return code Description
ProcessHandle did not have PROCESS_QUERY_INFORMATION access.
A new token handle could not be allocated.
ProcessHandle was not a valid handle.
The specified HandleAttributes did not include OBJ_KERNEL_HANDLE.
ProcessHandle was not a process handle.
The caller does not have the privilege (SeSecurityPrivilege) necessary to create a token handle with the access specified in the DesiredAccess parameter.
The process's memory quota is not sufficient to allocate the token handle.
The token handle could not be created.


ZwOpenProcessTokenEx opens the access token associated with a process and returns a handle for that token.

Any handle obtained by calling ZwOpenProcessTokenEx must eventually be released by calling ZwClose.

Driver routines that run in a process context other than that of the system process must set the OBJ_KERNEL_HANDLE attribute for the HandleAttributes parameter of ZwOpenProcessTokenEx. This restricts the use of the handle returned by ZwOpenProcessTokenEx to processes running in kernel mode. Otherwise, the handle can be accessed by the process in whose context the driver is running.

For more information about security and access control, see the documentation on these topics in the Windows SDK.

Note If the call to the ZwOpenProcessTokenEx function occurs in user mode, you should use the name "NtOpenProcessTokenEx" instead of "ZwOpenProcessTokenEx".
For calls from kernel-mode drivers, the NtXxx and ZwXxx versions of a Windows Native System Services routine can behave differently in the way that they handle and interpret input parameters. For more information about the relationship between the NtXxx and ZwXxx versions of a routine, see Using Nt and Zw Versions of the Native System Services Routines.


Windows version Available in Windows XP and later versions of Windows.
Target Platform Universal
Header ntifs.h (include Ntifs.h)
Library NtosKrnl.lib
DLL NtosKrnl.exe
DDI compliance rules PowerIrpDDis, HwStorPortProhibitedDDIs

See Also




Using Nt and Zw Versions of the Native System Services Routines