Which of the following are examples of passive attacks? Each correct answer represents a
complete solution. Choose all that apply.

A.
Dumpster diving

B.
Placing a backdoor

C.
Eavesdropping

D.
Shoulder surfing

Explanation:
In eavesdropping, dumpster diving, and shoulder surfing, the attacker violates the
confidentiality of a system without affecting its state. Hence, they are considered passive attacks.