Writing Secure Code

Chapter 7. Running with Least Privilege

There exists in the field of security the notion of always performing tasks with the least set of privileges required to perform those tasks. To cut a piece of plastic pipe, you could use a hacksaw or a chainsaw. Both will do the job, but the chainsaw is overkill. If you get things wrong, the chainsaw is probably going to destroy the pipe. The hacksaw will do the job perfectly well. The same applies to executable processes—they should run with no more privilege than is required to perform the task.

Running with least privilege also means using the elevated privileges for the shortest possible time. This reduces the window of exploit period. In Windows, you can enable privileges just prior to using them, perform ...