Which of the following specifically describes the exploitation of an interactive process to access otherwise restricted areas of the OS?

Pivoting is a post-exploitation technique used to access other systems on a network that are otherwise unreachable from the attacker's original position, not primarily about gaining higher privileges on the currently compromised system.

Process affinity is a scheduler property that binds a process or thread to a specific CPU or set of CPUs to optimize performance, and is unrelated to security exploitation or access control.

A buffer overflow is a specific type of vulnerability where a program attempts to write data beyond the allocated buffer, which can be a *method* used to achieve privilege escalation, but it is not the overarching description of accessing restricted areas via exploitation.

Privilege escalation is a type of attack where an attacker exploits a vulnerability in an application, service, or the operating system itself to gain elevated access rights, such as moving from a standard user to an administrator or system-level account. This allows the attacker to access otherwise restricted areas of the OS that were previously inaccessible, directly matching the scenario described.