Privilege bracketing
In computer security, privilege bracketing is a temporary increase in software privilege within a process to perform a specific function, assuming those necessary privileges at the last possible moment and dismissing them as soon as no longer strictly necessary, therefore ostensibly avoiding fallout from erroneous code that unintentionally exploits more privilege than is merited. It is an example of the use of principle of least privilege in defensive programming.
It should be distinguished from privilege separation, which is a much more effective security measure that separates the privileged parts of the system from its unprivileged parts by putting them into different processes, as opposed to switching between them within a single process.