CIA triad
Bob is trying to buy concert tickets to a concert that sells out in under 5 minutes. When ticket sales open, a million people attempt to purchase tickets and the system crashes. Unfortunately, Bob is now unable to buy concert tickets.
Availability
Bob sends Alice a check for $10. She then adds a "0" to the amount so now Bob has sent Alice a check for $100.
Integrity
Alice and Bob play computer games. Right as Alice is about to slay Bob's character with a +10 spell, Bob yanks her Ethernet cable.
Availability
Alice has online homework due at 2:00 PM and she is rushing to finish it. Right before she is about to submit, her power cuts out and Alice is no longer able to submit her homework by the due date.
Availability
Alice and Bob are students. Alice copies Bob's homework.
Confidentiality
Alice writes a private note in her diary and then locks it. Unfortunately, Bob finds the key and is able to open Alice's diary and read her private note.
Confidentiality
Bob and Alice are in the same class at school. When the teacher passes back the tests, he announces what each student received on the exam.
Confidentiality
Alice and Bob are trying to pass notes in class, but Mallory is sitting in between them. In order for Alice to get a note to Bob, Alice must pass it to Mallory and then Mallory must pass the note to Bob. One time, Bob needed help with Question #5 on the test. Alice handed Mallory a note to give to Bob that said, "The answer is true." Instead of handing this note to Bob, Mallory crumpled it up and handed him a new note that said, "The answer is false." Unfortunately, Bob got the question wrong and thought Alice had done it on purpose.
Integrity