Sample MCQ for phase test of STW120COM
1. Message _____ means that the data must arrive at the receiver exactly as sent. a)
Confidentiality
b) Integrity
c) Authentication
d) None of the above
2. _________ means that a sender must not be able to deny sending a message that he
sent.
a) Confidentiality
b) Integrity
c) Authentication
d) Non-repudiation
3. Which of the following pair of keys is used to create and verify the digital signature?
a) Sender’s private key and receiver’s public key
b) Sender’s public key and receiver’s private key
c) Sender’s private key and sender’s public key
d) Receiver’s private key and receiver’s public key
4. Fill in the gap: Computer security is a concoction of ____?
a) science
b) science and technology
c) science, technology and engineering
d) science, technology, engineering, and human factors
5. Which of the following is correct about the principle of Layered Security?
a) If you have direct access to the physical memory devices, you may be able to
bypass the access controls of the OS.
b) Applications need to take care of their own security requirements even if a
secure infrastructure is provided.
c) Both A and B
d) Neither A nor B
6. Using Rail Fence cipher and key n = 3, decrypt the following message via Zigzag.
“idadeneoeacenn”. Which of the following is correct?
a) One more time I go
b) I need a one dance
c) Even when I am away
d) Got a Hennessy in my hand
7. Which of the following are computer security issues?
a) Mistakes made by human operators
b) Accidental breakdown of communications
c) Intentional computer system failures
d) All of the above
8. Which of the following is used to achieve diffusion in DES?
a) Permutation
b) Expansion
c) S‐box
d) All of the above
9. Which of the following combination is a form of multi-factor authentication?
a) PINs and passwords
b) Smart cards and passwords
c) Key tokens and smart cards
d) None of the above
10. What is the size of DES sub-key?
a) 48 bits
b) 16 bits
c) 64 bits
d) 56 bits
11. Using Vigenere cipher and keyword “night”, encrypt the message “Good morning”.
Which of the following is the correct cipher text?
a) Kapynbkdbst
b) Mppeelrnson
c) Toos iworinf
d) Twuk fbztpgt
12. Which two ingredients are used for digital signature?
a) DES and SHA128
b) RSA and SHA512
c) AES and RC2
d) RSA and PKCS1
13. Based on the Access Control (AC) model, given the following access control statement,
which is the subject?
AC statement: Alan Fisher, with his user identity being Afisher, runs a program, called
user-management.exe that reads data from file /etc/passwd.
a) Alan Fisher
b) Afisher
c) user-management.exe
d) /etc/passwd
14. Substitution ciphers
a) Replace one character with another
b) Swap each character with the next one
c) Swap each character with the previous one
d) Swap each character with the next one or the previous one
15. A Linux system contains both /etc/passwd and /etc/shadow documents. Which of the
following statement is correct?
a) Users’ passwords are stored in /etc/passwd in an encrypted format
b) Users’ passwords are stored in /etc/shadow in a plain-text format
c) Every user can read /etc/shadow
d) Every user can read /etc/passwd 16. What is the key size of AES
encryption?
a) 128 bits
b) 192 bits
c) 256 bits
d) All of the above
17. An ________ takes some number of input bits, m, and transforms them into some
number of output bits, n, where n is not equal to m.
a) S-box
b) T-box
c) P-box
d) None of the above
18. RSA _________ be used for digital signatures.
a) Can
b) Cannot
c) Must
d) Must not
19. In which year were the first electronic computers built, and in which year can computer
security trace its origins back to?
a) 1940s and 1950s respectively
b) 1950s and 1960s respectively
c) 1940s and 1960s respectively
d) 1930s and 1940s respectively
20. Which of the following statements is correct about the ‘groups’ on Linux systems?
a) A user can be in one group only
b) A user can be in one or many groups
c) If a user is in more than one group, at any time this user can be in one or many
primary groups
d) A user can be in only one supplementary group
21. Which of the following is correct about authentication?
a) Among all the factors of authentication, ‘something you know’, such as
passwords and PINs, are considered the weakest category of the factors.
b) Among all the factors of authentication, ‘something you are’, such as retinas and
DNAs, are considered the strongest forms of authentication.
c) Behavioral biometrics, such as voice recognition and keystrokes on a keyboard,
are considered forms of authentication.
d) All of the above
22. The first computer virus is
a) The famous
b) HARLIE
c) PARAM
d) Creeper
23. Which of the following modes need an Initialization Vector (IV)? Select all that apply
a) Electronic Code Book
b) Cipher Block Chaining
c) Cipher Feedback
d) Output feedback
24. STRIDE (Spoofing, Tampering, Repudiation, Information Disclosure, Denial of service
and Elevation of Privilege) is a model developed by Microsoft for analyzing computer
security threats. Which category is related to the corruption of resources?
a) Spoofing
b) Tampering
c) Information Disclosure
d) Both b and c
25. A(n) ______ algorithm transforms ciphertext to plaintext.
a) Encryption
b) Decryption
c) Either (a) or (b)
d) Neither (a) nor (b)
26. A(n) _____ is a trusted third party that assigns a symmetric key to two parties.
a) KDC
b) CA
c) KDD
d) None of the above
27. What is the maximum character Linux supports in its filenames?
a) 8
b) 128
c) 256
d) Unlimited
28. Message _______ means that the receiver is ensured that the message is coming from
the intended sender, not an imposter.
a) Confidentiality
b) Integrity
c) Authentication
d) None of the above
29. ________ DES was designed to increase the size of the DES key
a) Double
b) Triple
c) Quadruple
d) none of the above
30. ____________ mode is similar to Cipher Feedback, except that the input to the
encryption algorithm is the preceding algorithm output.
a) Counter
b) Output Feedback
c) Cipher Feedback
d) Cipher Block Chaining
31. DES has an initial and final permutation block and _________ rounds.
a) 14
b) 15
c) 16
d) None of the above
32. A(n) _______ is a keyless transposition cipher with N inputs and M outputs that uses a
table to define the relationship between the input stream and the output stream. a) Sbox
b) P-box
c) T-box
d) None of the above
33. Which of the following allows for parallel encryption?
a) Output feedback
b) Electronic Codebook
c) Cipher Block Chaining
d) Cipher Feedback
34. At encryption side in RSA, which formula is used?
a) Me mod(n)
b) Md mod(ɸ)
c) Cd mod (n)
d) Mn mod (ɸ)
35. Which of the following modes “convert” the block cipher to a stream cipher? Select all
that apply
a) Cipher Feedback
b) Electronic Codebook
c) Output feedback
d) Both a and c
36. In an asymmetric‐key cipher, the receiver uses the ______ key to decrypt.
a) Private
b) Public
c) Either a or b
d) Neither a nor b
37. At decryption side in RSA, which formula is used?
a) Me mod(n)
b) Md mod(ɸ)
c) Cd mod (n)
d) Mn mod (ɸ)
38. A stream cipher encrypts ____ at a time.
a) N bits
b) 64 bits
c) 64 bits, 128 bits, or 256 bits
d) One bit
39. It is not possible for two different inputs to produce the same hash
a) True
b) False
40. Using Ceasar Cipher and key n=6, encrypt the message "You Are Half World Away".
Which of the following is correct?
a) eua gxk ngrl cuxrj gcge
b) eua gxk larr cuxrj gcge
c) hghe O roqk euax yzerk
d) eua gxk g skyy
41. Which of the following belongs to symmetric encryption? Select all that applies.
42.
a) AES
b) RSA
c) DES
d) RC4
43. The ___________ criterion ensures that we cannot find two messages that hash to the
same digest
a) Weak collision resistance
b) Strong collision resistance
c) Avalanche effect
d) None of the above
44. Which is the largest disadvantage of symmetric encryption?
a) More complex mathematics
b) Problem of the secure transmission of the secret key
c) Is not used any more
d) More time-consuming calculations
45. The ________ property states that even a 1-bit difference in the input of two string
produces completely different hash
a) Weak collision resistance
b) Strong collision resistance
c) Avalanche effect
d) Strobe effect
46. Hash function is a ____. Select all if applies.
a) Two-way function
b) One-way function
c) Compressive function
d) All of the above
47. For a client-server authentication, the client requests from the KDC a ________ for
access to a specific asset.
a) Token
b) Local
c) Ticket
d) User
48. What is the goal of social engineering?
a) Sabotage a person's social media
b) To gain vital personal information
c) To catfish someone
d) To build trust
49. An authenticator in Kerberos includes information about
a) IP
b) Name, IP
c) Timestamp
d) All the above
50. An email claiming that you have won the lottery, as long as you fill out the
corresponding information, is an example of what type social engineering attack? a)
Baiting
b) Phishing
c) Piggybacking
d) Email from a friend
51. The output of the encryption function is fed back to the shift register in Output
Feedback mode, whereas in ___________ the cipher text unit is fed back to the shift
register.
a) Counter mode
b) Cipher Block Chaining mode
c) Cipher Feedback mode
d) Electronic Codebook mode
***Best of Luck***