Computer Security Questions and Answers

Answer: C

Correct answer: Creeper

Creeper, written in 1971 for the ARPANET, is generally counted the first computer virus: it copied itself between DEC PDP-10 machines and displayed the message I'm the creeper, catch me if you can. Blaster, Sasser and ILOVEYOU are all much later, from 2000 onwards.

Answer: B

Correct answer: The Information Technology Act, 2000

The Information Technology Act, 2000 is India's principal statute on electronic records, digital signatures and cybercrime; it was substantially amended in 2008. The other two titles are invented.

Answer: C

Correct answer: DoS attacks

A denial of service attack is a recognised class of computer threat: it floods a system until it can no longer serve anyone. Phishing is a technique rather than a class, and soliciting and stalking are social offences rather than attacks on a computer.

Answer: B

Correct answer: Brain

Brain, written in Pakistan in 1986, was the first boot sector virus for the PC: it replaced the boot sector of a floppy disk and spread whenever an infected disk was used to start a machine. Elk Cloner, from 1982, was earlier but infected the Apple II.

Answer: A

Correct answer: Modification detection code (MDC)

A plain hash, computed without a key, is a modification detection code: it detects change but proves nothing about origin, since anyone can recompute it. Adding a key turns it into a MAC.

Answer: A

Correct answer: True

Both are ways of getting a file onto the machine and running it, which is all malware needs. An attachment is simply a file delivered by mail rather than fetched from a site, so the risk is the same in kind.

Answer: C

Correct answer: During a particular date or time

A time bomb is a logic bomb whose trigger is the clock or the calendar, so it fires on a chosen date or at a chosen time - the Friday the 13th and Michelangelo viruses are the classic examples. A trigger on some other condition makes it a logic bomb rather than a time bomb.

Answer: B

Correct answer: MITM

In a man-in-the-middle attack the attacker interposes a server of his own between the two parties and relays their traffic, so each believes it is talking to the other while everything passes through him. The other three are protocols, not attacks.

Answer: D

Correct answer: Worm

The distinguishing property is independence: a worm propagates itself across a network without needing a host program or any action by a user, whereas a virus can only spread when the program it has infected is run.

Answer: C

Correct answer: Changed

A hash function gives integrity: any alteration to the message produces a different digest, so a matching digest shows the message has not been changed. It says nothing about who sent it or whether it was intercepted.