Replay, masquerade, modification of messages, and denial of service are examples of what type of attacks?

• A. active
• B. passive
• C. theoretical
• D. procedural

Answer: (A)

The correct answer identifies these examples as active attacks because they involve unauthorized actions taken to manipulate or disrupt data and resources. In active attacks, the attacker is directly engaged in altering the communication process or the data itself, such as replaying messages to gain unauthorized access, masquerading as another user to exploit a system, modifying messages to change their meaning or purpose, or initiating a denial of service to disrupt operations.

Active attacks are characterized by their immediate impact on the target, aiming to change the state of the system or data. This stands in contrast to passive attacks, which involve eavesdropping or monitoring communications without altering them, indicating that the attacker's objective is different in the two cases. The terms theoretical and procedural do not apply to the classification of direct actions taken by an attacker, making them irrelevant in this context.