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1
Q

What is the primary objective of an Advanced Persistent Threat (APT)?

A

To gain stealthy, long-term access to a targeted system for data exfiltration.

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2
Q

An APT campaign can often exist for several _____ and may be well funded.

A

years

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3
Q

What is a common entry point exploited by APTs to penetrate a system?

A

The end user (insider), often through vulnerabilities like poor passwords.

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4
Q

How do APTs often evade detection by security tools like firewalls and SIEMs?

A

By creating network traffic that is purposely designed to look like legitimate traffic.

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5
Q

What is the ‘Reconnaissance’ stage in an APT attack?

A

The phase where attackers gather as much information as possible about the target’s systems, processes, and potential entry points.

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6
Q

What occurs during the ‘Initial Compromise’ stage of an APT attack?

A

The attacker gains their first access or ‘foothold’ in a system, often through social engineering.

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7
Q

The APT stage where an attacker expands access across systems, compromises additional devices, or increases permissions is known as _____.

A

Lateral Movement

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8
Q

What is ‘Data Exfiltration’ in the context of an APT?

A

The process of sending stolen data through outbound traffic from the compromised network to the attacker’s devices.

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9
Q

What are the two key activities in the final stage of an APT attack cycle?

A

Maintenance of access to the systems and concealment of any evidence of the compromise.

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10
Q

In Unix-like systems, what are the three user classifications for file permissions?

A

Owner, Group, and World (or Other).

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11
Q

What do the characters ‘r’, ‘w’, and ‘x’ represent in Unix file permissions?

A

Read, write, and execute permissions, respectively.

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12
Q

What permissions are represented by the notation rwxrw-r--?

A

The owner has read, write, and execute; the group has read and write; others have read-only.

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13
Q

In the context of digital images, what is a bitplane?

A

A matrix comprising the i-th bit of each pixel in a digital image for a specific colour channel.

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14
Q

In the BPCS steganography algorithm, how is the complexity of a segment determined?

A

By calculating the ratio of the segment’s border changes to the maximum possible border changes (a checkerboard pattern).

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15
Q

According to the BPCS algorithm, a segment is considered ‘complex’ enough to hide data if its complexity value is greater than _____.

A

0.3

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16
Q

If a payload block in BPCS is not complex, what operation is performed before hiding it?

A

It is conjugated by performing an exclusive OR (XOR) operation with a checkerboard pattern.

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17
Q

What is the definition of a biometric trait for user access control?

A

A sufficiently distinctive trait that can be measured, quantified, and stored for authentication.

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18
Q

What are the two main categories of biometrics?

A

Physical and behavioural.

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19
Q

What is the ‘Enrolment’ stage in a biometric system?

A

The initial process where a user’s biometric trait is captured and a template is extracted and stored.

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20
Q

Metric: False Accept Rate (FAR)

A

Definition: A measure of the likelihood that a biometric system will incorrectly accept an unauthorised user.

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21
Q

Metric: False Reject Rate (FRR)

A

Definition: A measure of the likelihood that a biometric system will incorrectly reject an authorised user.

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22
Q

What does a Receiver Operating Characteristic (ROC) curve plot in biometrics?

A

The True Accept Rate (TAR) against the False Accept Rate (FAR) at various threshold settings.

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23
Q

Which biometric method is claimed to be highly accurate, producing only 1 in 1-2 million false positives?

A

Iris recognition.

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24
Q

Which biometric method is considered more invasive than iris scanning and can be affected by disease over time?

A

Retinal scanning.

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25
In fingerprint recognition, ridges and valleys form basic patterns such as arches, loops, and _____.
whorls
26
What are the two key metrics in keystroke dynamics, a form of behavioural biometrics?
Dwell time (how long a key is pressed) and flight time (time between key presses).
27
Vulnerability: Broken Authentication
Definition: Errors in the implementation of authentication mechanisms, such as session timeouts or weak password management.
28
How can the risk of Sensitive Data Exposure be mitigated?
By encrypting or hashing sensitive data using appropriate methods and not storing unnecessary data.
29
What is an XML External Entities (XXE) vulnerability?
A vulnerability where an XML processor insecurely evaluates external entities included in an XML document.
30
An attack where a user can access unauthorised data by manipulating a URL parameter, such as an ID number, is known as an _____.
Insecure Direct Object Reference
31
Vulnerability: Missing Function Level Access Control
Definition: When an application fails to check authorisation before fulfilling a request for specific functionality.
32
What is 'Security Misconfiguration'?
When a system's security is weakened due to issues like not changing default credentials, leaving debugging modes on, or failing to apply patches.
33
Term: Steganography
Definition: The practice of concealing a message, file, or other data within another, non-secret file or object.
34
How does steganography differ from cryptography?
Cryptography obscures the content of a message, whereas steganography conceals the very existence of the message.
35
In the Least Significant Bit (LSB) steganography method, how is data hidden?
By replacing the least significant bit of each colour value in the pixels of a cover image with the bits of the secret message.
36
What is the purpose of the Cyber Kill Chain framework?
To identify and prevent cyber intrusions by breaking down an attack into distinct stages.
37
What occurs during the 'Weaponisation' stage of the Cyber Kill Chain?
An attacker combines an exploit with a payload (like malware) to create a deliverable 'weapon'.
38
The 'Delivery' stage of the Cyber Kill Chain involves transmitting the weapon to the target. Give an example of a delivery method.
Spear phishing emails, malicious USB drives, or exploiting a web vulnerability like SQL injection.
39
What happens during the 'Exploitation' stage of the Cyber Kill Chain?
The malicious code is executed on the victim's system, triggering the vulnerability.
40
What is the purpose of the 'Command and Control' (C2) stage in the Cyber Kill Chain?
The attacker establishes remote access and control over the compromised machine, often using a Remote Access Trojan (RAT).
41
What is the final stage of the Cyber Kill Chain, where the attacker's ultimate goals are achieved?
Actions on Objectives.
42
What is a Demilitarised Zone (DMZ) in network architecture?
A perimeter network that sits between an organisation's internal private network and the external untrusted network (like the internet).
43
How does an Intrusion Prevention System (IPS) differ from an Intrusion Detection System (IDS)?
An IDS monitors and alerts on potential violations, while an IPS can additionally take action to prevent the violation.
44
What problem does the Diffie-Hellman key exchange solve?
It allows two parties to establish a shared secret (a private symmetric key) over an insecure communication channel.
45
What is a digital signature?
A cryptographic mechanism that uses a hash of a document encrypted with the sender's private key to ensure authenticity and integrity.
46
To verify a digital signature, the recipient decrypts the encrypted hash using the sender's _____ key.
public
47
Property: Strong Collision Resistance
Definition: A property of a cryptographic hash function stating that it is computationally infeasible to find two different messages that hash to the same value.
48
A firewall policy that denies all traffic by default and only permits specifically allowed traffic is known as a _____ policy.
whitelist (or deny by default)
49
What is the function of a proxy server?
It acts as an intermediary for requests from clients seeking resources from other servers, hiding the client's IP address.
50
What is the primary purpose of the Kerberos protocol?
To provide strong, mutual authentication for client/server applications by using secret-key cryptography.
51
In Kerberos, what is the role of the Authentication Server (AS)?
It authenticates the user at the start of a session and issues a Ticket-Granting Ticket (TGT).
52
In Kerberos, what does the Ticket-Granting Server (TGS) do?
It issues service tickets to clients who present a valid Ticket-Granting Ticket (TGT).
53
What is a replay attack?
An attack where a valid data transmission (like authentication credentials) is intercepted and maliciously repeated or delayed.
54
How does a VPN create a secure connection over a public network like the internet?
Through a process called tunnelling, where packets are encapsulated within other packets and encrypted.
55
What is the core principle of the CIA Triad in information security?
To ensure the Confidentiality, Integrity, and Availability of information.
56
Term: Confidentiality (CIA Triad)
Definition: The principle that information should only be accessible to authorised users.
57
Term: Integrity (CIA Triad)
Definition: The principle that information should not be altered or destroyed in an unauthorised manner.
58
Term: Availability (CIA Triad)
Definition: The principle that systems and information should be accessible and usable upon demand by an authorised user.
59
What is the difference between a threat and a vulnerability?
A vulnerability is a weakness in a system, while a threat is a potential danger that could exploit that vulnerability.
60
What does the STRIDE framework stand for?
Spoofing, Tampering, Repudiation, Information disclosure, Denial of service, Elevation of privilege.
61
In STRIDE, the threat of Spoofing relates to which security property?
Authentication.
62
In STRIDE, unauthorised modification of data is classified as _____ and violates the property of Integrity.
Tampering
63
In STRIDE, what is Repudiation?
A threat where a user denies having performed an action, violating the principle of non-repudiation.
64
In STRIDE, the threat of exposing sensitive information to unauthorised parties is known as _____.
Information disclosure
65
What is a Denial of Service (DoS) attack?
An attack designed to make a machine or network resource unavailable to its intended users.
66
How does a Distributed Denial of Service (DDoS) attack differ from a DoS attack?
A DDoS attack uses multiple compromised computer systems (a botnet) as the source of the attack traffic.
67
What is a SYN Flood attack?
A DoS attack where an attacker sends a succession of SYN requests to a target's system in an attempt to consume server resources.
68
A collection of internet-connected devices infected with malware that allows an attacker to control them is known as a _____.
botnet
69
What is port scanning?
The process of sending client requests to a range of server port addresses on a host, with the goal of finding an active port.
70
In public-key cryptography, a message is encrypted using the recipient's _____ key.
public
71
In public-key cryptography, a message is decrypted using the recipient's _____ key.
private
72
The RSA algorithm's security relies on the computational difficulty of what mathematical problem?
Factoring the product of two large prime numbers.
73
What is a Cross-Site Scripting (XSS) attack?
An attack where malicious client-side scripts are injected into web pages viewed by other users.
74
What is the difference between Stored XSS and Reflected XSS?
In Stored XSS, the malicious script is permanently stored on the target server, while in Reflected XSS, it is delivered via a link or request.
75
How can HTML encoding help prevent XSS attacks?
By converting special characters (like '<' and '>') into their HTML entity equivalents (like '<'), preventing the browser from executing them as code.
76
What is an Insecure Deserialization vulnerability?
A flaw that occurs when an application deserializes malicious or manipulated objects, potentially leading to remote code execution.
77
What is a SQL injection attack?
An attack technique used to interfere with the queries that an application makes to its database, often by inserting malicious SQL code.
78
What is the purpose of the `OR '1'='1'` payload in a SQL injection attack?
To create a condition that is always true, often bypassing authentication checks by making the WHERE clause of a query evaluate to true.
79
How do prepared statements (or parameterised queries) mitigate SQL injection vulnerabilities?
They separate the SQL query structure from the user-supplied data, ensuring the data is treated as a literal value and not as executable code.
80
What are the three main authentication factors?
Something you know (knowledge), something you have (token), and something you are (biometrics).
81
What is multi-factor authentication (MFA)?
An authentication method that requires the user to provide two or more verification factors from different categories to gain access.
82
In block ciphers, what is the purpose of a mode of operation like Cipher Block Chaining (CBC)?
To securely encrypt amounts of data larger than a single block, ensuring identical plaintext blocks do not result in identical ciphertext blocks.
83
What is a major security flaw of the Electronic Code Book (ECB) mode of operation?
It encrypts identical plaintext blocks into identical ciphertext blocks, which can reveal patterns in the data.
84
What is the purpose of an S-box (Substitution-box) in a block cipher?
To provide non-linearity and confusion by substituting a small block of bits with another block of bits.
85
What is the purpose of a P-box (Permutation-box) in a block cipher?
To provide diffusion by permuting or transposing bits across its input.
86
The AES algorithm operates on a 4x4 matrix of bytes known as the _____.
state
87
The Blowfish algorithm is a type of _____ cipher structure.
Feistel
88
How does a stream cipher operate?
It encrypts plaintext digits one at a time (e.g., bit by bit) by combining them with a keystream.
89
What is the function of a key schedule in a block cipher?
It is an algorithm that takes the initial secret key and expands it into a set of round keys used in each round of encryption.
90
In Transport Layer Security (TLS), what is the role of a Certificate Authority (CA)?
To issue and digitally sign certificates that verify the ownership of a public key by a named subject.
91
What security property does (Perfect) Forward Secrecy provide?
It ensures that if a long-term secret key is compromised, past session keys cannot be derived, protecting past communications.
92
Term: Cryptographic Entropy
A measure of the unpredictability or randomness of a piece of data, often used to assess password strength.
93
What is packet sniffing?
The act of intercepting and logging traffic that passes over a digital network or part of a network.
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