BSCS Computer Security and Cybersecurity 1 — Questions and Answers
Question 1: Which of the following best describes the CIA triad in information security?
- Confidentiality, Integrity, Availability (Correct answer)
- Control, Identification, Authorization
- Cryptography, Intrusion, Authentication
- Configuration, Implementation, Access
Correct answer: Confidentiality, Integrity, Availability
The CIA triad stands for Confidentiality, Integrity, and Availability — the three foundational principles guiding information security design.
Question 2: In symmetric encryption, which statement is true?
- Two different keys are used for encryption and decryption
- The same key is used for both encryption and decryption (Correct answer)
- No key is needed for decryption
- The public key encrypts and the private key decrypts
Correct answer: The same key is used for both encryption and decryption
Symmetric encryption uses a single shared key for both encrypting and decrypting data, unlike asymmetric encryption which uses mathematically linked key pairs.
Question 3: What type of attack involves an attacker secretly inserting themselves between two communicating parties to intercept or alter messages?
- Replay attack
- Man-in-the-Middle (MITM) attack (Correct answer)
- Denial of Service attack
- SQL injection attack
Correct answer: Man-in-the-Middle (MITM) attack
A Man-in-the-Middle (MITM) attack occurs when an attacker covertly intercepts and potentially modifies communications between two parties who believe they are communicating directly.
Question 4: Which hashing algorithm produces a 256-bit digest and is widely used in TLS, digital signatures, and blockchain applications?
- MD5
- SHA-1
- SHA-256 (Correct answer)
- DES
Correct answer: SHA-256
SHA-256 is part of the SHA-2 family and produces a 256-bit hash, making it collision-resistant and suitable for cryptographic applications unlike the deprecated MD5 and SHA-1.
Question 5: What is a buffer overflow attack?
- An attack that floods a network with excessive traffic
- An attack where input data exceeds a buffer's capacity, potentially overwriting adjacent memory and hijacking execution (Correct answer)
- An attack that intercepts data packets during transmission
- An attack that repeatedly guesses passwords until one succeeds
Correct answer: An attack where input data exceeds a buffer's capacity, potentially overwriting adjacent memory and hijacking execution
A buffer overflow occurs when a program writes more data to a buffer than allocated, overwriting adjacent memory and potentially redirecting execution to attacker-controlled code.
Question 6: Which access control model assigns permissions based on a user's job function within an organization?
- Discretionary Access Control (DAC)
- Mandatory Access Control (MAC)
- Role-Based Access Control (RBAC) (Correct answer)
- Attribute-Based Access Control (ABAC)
Correct answer: Role-Based Access Control (RBAC)
Role-Based Access Control (RBAC) grants permissions based on defined roles such as 'admin' or 'accountant,' simplifying management by assigning users to roles rather than individual permissions.
Question 7: What is the primary purpose of a digital signature?
- To encrypt the full message content for confidentiality
- To verify the sender's identity and ensure the message has not been altered (Correct answer)
- To compress the message for faster transmission
- To hide the recipient's identity from network observers
Correct answer: To verify the sender's identity and ensure the message has not been altered
A digital signature uses the sender's private key to create a verifiable proof of identity (authentication) and detect any modification of the message (integrity).
BSCS Computer Security and Cybersecurity 1
Which of the following best describes the CIA triad in information security?