This section contains carefully selected MCQs and Previous Year Questions with explanations to help students understand concepts and prepare effectively for examinations, interviews, and competitive tests.
Q: 1Identify the oldest phone hacking technique used by hackers to make free calls?
Option B
Phreaking is an early phone hacking method from the 1960s and 70s where hackers used special sounds to trick telephone systems. They played a 2600 Hz tone to control the phone switches and make free long-distance calls. Tools called "blue boxes" were made to create these tones, and famous phreakers like John Draper (“Captain Crunch”) used a cereal box whistle that made the same tone.
Q: 2During May 2017, a very popular malware infected almost 2 lakh computers around the world. It demanded payments in Bitcoin crypto currency. It made its victims cry. It is known as _____________.
Option A
WannaCry was a ransomware attack that occurred in May 2017, infecting over 2,00,000 computers across 150 countries. It encrypted users’ data and demanded payment in Bitcoin cryptocurrency to restore access, hence the name “WannaCry” because victims were left helpless.
Q: 3Which one of the following is usually used in the process of Wi-Fi hacking?
Option A
Aircrack-ng is a widely used toolset for Wi-Fi hacking and security testing. It includes tools for capturing network traffic, testing wireless card capabilities, and cracking WEP (Wired Equivalent Privacy), WPA (Wi-Fi Protected Access), and WPA2 encryption keys.
It supports various attacks such as deauthentication and replay attacks to capture handshake data needed for cracking passwords. This tool is popular among security professionals and hackers for analyzing and testing Wi-Fi network security.
Wireshark is a powerful packet analyzer useful for inspecting network traffic and can assist in wireless troubleshooting or analysis, but it is not primarily a Wi-Fi cracking tool.
Q: 4Which amongst the following is not a way to protect the system from malware?
Option A
OPENING POP-UPS is not a way to protect your system, in fact, it is one of the most common ways malware spreads. Pop-ups may contain malicious links, fake ads, or phishing content that can install harmful software on your device.
To stay protected from malware, never click on suspicious pop-ups, use firewalls and antivirus software, and regularly back up important data.
Q: 5The __________ keyboard of an operating system uses a fixed QWERTY key layout. This can be exploited by keylogger but are still safe than normal keyboard hardware.
Option A
The On-Screen Keyboard is a Virtual Keyboard provided by an operating system that displays QWERTY keys on the screen that allows users to input text by clicking keys using a mouse or touch input instead of a physical keyboard.
Although keyloggers can exploit it by recording screen activities, it is still safer than hardware keyboards, which can be compromised by physical keyloggers.
Q: 6_________ is a complete software of a third party that is installed on the host computer and can be used by the browser for multiple functionalities.
Option C
A Plug-In is a complete software component developed by a third party that is installed on a host application, such as a web browser, to extend its capabilities.
Plug-Ins allow browsers to perform additional functions like playing videos, displaying PDFs, or running multimedia content. Examples include Adobe Flash Player, Java Plug-in, PDF Viewer etc.
Plug-Ins differ from Add-Ons or Extensions, which are usually smaller tools that modify or enhance the browser’s behavior, while plug-ins provide additional functionality through external software integration.
Q: 7Which phase is not included in virus life cycle?
Option C
A Computer Virus is a type of malicious software that attaches itself to files or programs and can spread from one system to another. Just like a biological virus, it has a life cycle made up of different stages.
| Phase | Description |
|---|---|
| Dormant Phase | The virus stays inactive, waiting for specific conditions to occur like date, event, or user action. |
| Propagation Phase | The virus spreads by making copies of itself and attaching to files, programs, or boot sectors. |
| Triggering Phase | The virus is activated when certain conditions are met, e.g., opening a file, reaching a set date. |
| Execution Phase | The malicious payload runs, performing harmful actions such as deleting data, corrupting files, or displaying messages. |
Q: 8__________ is a network security system designed to protect a trusted private network from an untrusted outside network to which it is connected.
Option C
A Firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Its primary purpose is to protect a trusted internal (LAN) network from untrusted external networks like the Internet.
Firewalls can be hardware, software, or a combination of both, and act as a barrier or gatekeeper between networks by allowing or blocking data packets depending on security policies.
Q: 9Which of the following attack is used for identity theft?
Option A
Phishing is when someone tricks you to give your personal information like passwords, bank details, or ID numbers by sending fake emails, messages, or websites that look real. Hackers use this stolen information to steal your identity, make purchases, or commit fraud.
Q: 10___________ is another term for antivirus software.
Option A
Antivirus software is also called Antimalware, because it protects the system not only from viruses but also from other malicious software like worms, trojans, spyware, and ransomware.
| MALWARE TYPE | EXPLANATION |
|---|---|
| Virus | Attaches to files or programs and spreads when the file is run. |
| Worm | Spreads automatically across computer or networks without user action. |
| Trojan Horse | Looks like a safe program but secretly does harmful things. |
| Spyware | Secretly monitors user activity and steals information. |
| Adware | Displays unwanted ads (advertisements), sometimes tracks browsing. |
| Ransomware | Locks files or systems and demands payment to unlock them. |
| Rootkit | Hides itself and other malware, giving attackers control. |
| Keylogger | Records all keystrokes to steal information like passwords. |
| Backdoor | Creates a hidden way to access a computer system. |
| Logic Bomb | Triggers malicious actions when specific conditions are met. |
Q: 11Consider Column – I and Column – II in context of malwares.
| Column – I | Column – II |
|---|---|
| a. Rootkit | i. An infected machine activated to launch attacks on other machines. |
| b. Zombie | ii. Appears to be useful, but also has a hidden malicious function. |
| c. Spyware | iii. Collects information and transmits it to another system. |
| d. Trojan Horse | iv. Set of hacker tools used after breaking into a computer system and gaining root-level access. |
Which of the following is the most suitable match of Column – I and Column – II?
Option A
| Malware Type | Description |
|---|---|
| Virus | Infects files and programs, spreads when infected files are shared or executed. |
| Worm | Self-replicating malware that spreads across networks without user action. |
| Trojan Horse | Appears as legitimate (genuine) software but secretly creates backdoors or installs malware. |
| Rootkit | Hides deep in the OS, modifies system functions, and gives attackers administrator control. In other word, set of hacker tools installed after gaining root-level access to a system, allowing attackers to hide their presence and control the system. |
| Spyware | Monitors user activities, stealing data such as browsing history, keystrokes, and credentials. |
| Ransomware | Encrypts files and demands payment for the decryption key. |
| Zombie | An infected machine that can be remotely controlled to launch attacks, often as part of a botnet. |
| Adware | Displays intrusive advertisements, often bundled with free software. |
| Keylogger | Records user keystrokes to steal sensitive information like passwords and credit card details. |
Q: 12An unauthorized real – time interception or monitoring of private communication between two entities over a network is called –
Option B
In network security, communication between two devices can be intercepted by malicious users. Eavesdropping is the unauthorized real-time interception or monitoring of private communication between two entities over a network. It can involve listening to voice calls, reading emails or data transmissions without consent, exploiting unsecured or weakly secured communication channels.
Q: 13Which attack blocks a legitimate user (मान्य उपयोगकर्ता) from using computer?
Option D
A Denial of Service (DoS) attack is a type of cyberattack that aims to make a computer system or network unavailable to its legitimate users. It does this by overloading the system with excessive requests, causing it to slow down or crash completely.
Q: 14To verify a digital signature, we need the _____________.
Option B
In public key cryptography, a Digital Signature is created by the sender using their private key (Sender Private Key). To verify that the signature is authentic and that the message has not been altered, the receiver uses the Sender’s Public Key. This ensures the signature was indeed generated by the sender and provides authentication and integrity.
Q: 15Which of the following statements are true regarding firewalls?
A. Only the packets from trusted source address can enter the organization's network.
B. It is important to have firewalls to prevent the network from unauthorized access.
C. A firewall can be implemented using hardware or software or the combination of both.
D. A firewall can not be implemented using software.
Option A
A Firewall is a network security device or software that acts as a barrier between a trusted internal network and an untrusted external network, like the internet.
Its main purpose is to monitor data packets entering or leaving the network and decide whether to allow or block them based on predefined security rules.
Firewalls help protect systems from hackers, viruses, and unauthorized access. They can be implemented using hardware, software, or both, depending on the system’s security needs.
Firewalls ensure that only packets from trusted source addresses are allowed to enter the organization’s network.
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