Which of the following best describes an injection attack?

An injection attack specifically refers to a method where an attacker inserts or injects malicious code into an application or server to manipulate it into executing unintended commands or actions. This type of attack typically exploits vulnerabilities in an application that fail to properly validate user input.

By injecting malicious payloads, such as SQL queries in the case of SQL injection attacks, the attacker can gain unauthorized access to data, execute administrative operations, or even take control of the server. The fundamental aspect of an injection attack is this insertion of harmful code that exploits existing weaknesses, making the chosen response the most accurate definition of the term.

The other options illustrate different types of cyber threats or attacks, but they do not align with the specific mechanism of injecting code to execute malicious actions.