What is privilege escalation?

Privilege escalation refers to the act of exploiting a flaw or vulnerability in a system to gain elevated access to resources that are normally protected from the user. This often involves an attacker leveraging a design flaw, configuration mistake, or security vulnerability to gain higher permissions than they are intended to have.

When considering the options, gaining unauthorized access to a system (the first option) may describe a general hacking attempt but does not specifically address the context of increasing one's level of access. Implementing stronger security protocols (the third option) goes against the essence of privilege escalation, as this action would fortify a system rather than exploit it. Reducing user permissions (the fourth option) is the opposite of what occurs during privilege escalation, where the goal is to increase privileges rather than reduce them.

Thus, the focus on exploiting a design flaw to access restricted resources accurately defines privilege escalation, making it the correct choice.