One of the predefined security access masks is
You see it used in defining the
_ALL_ACCESS masks for
Here are just a few examples:
#define PROCESS_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED | SYNCHRONIZE | \ 0xFFF) #define EVENT_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SYNCHRONIZE|0x3) #define FILE_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED | SYNCHRONIZE | 0x1FF)
STANDARD_RIGHTS_REQUIRED mask is meant to be used
when defining access masks for object types.
I'm guessing it's called
it's the set of access masks that all securable objects must support.
Look at the documentation
or just at the definition:
#define DELETE (0x00010000L) #define READ_CONTROL (0x00020000L) #define WRITE_DAC (0x00040000L) #define WRITE_OWNER (0x00080000L) #define STANDARD_RIGHTS_REQUIRED (0x000F0000L)
STANDARD_RIGHTS_REQUIRED is just
an abbreviation for the union of the four access bits
DELETE | READ_CONTROL | WRITE_DAC | WRITE_OWNER.
Now that you see what it's for, you can also see what it's not for: You're not expected to pass it as the mask of requested access bits when you attempt to open an object. In other words, the following is wrong:
// wrong! HANDLE hProcess = OpenProcess(dwProcessId, FALSE, STANDARD_RIGHTS_REQUIRED | PROCESS_QUERY_INFORMATION);
The person writing this code probably thought,
"Well, I just want to be able to query information, so I need to
There's this other thing here called
since it's required, I'll pass that too."
The "required"ness of
apply to you, the program opening the object.
It applies to the person who is designing the object.
Your attempt to be a "good security citizen" and ask only for the
access you need (namely,
has backfired due to the addition of
If you ask for
you are asking for everything.
Why is that?
If you have
WRITE_DAC permission, that means that you
have permission to
change the security descriptor on the object,
at which point you totally 0wnz0r it.
PROCESS_VM_WRITE access but the security
descriptor doesn't let you?
Just set a new security descriptor that grants you
PROCESS_ALL_ACCESS to the process object.
Tada! You now have all the access in the world.
Moral of the story:
Don't ask for
because only somebody with full control will be able to get it.
Ask for what you actually want.