Cybersecurity — Complete Study Notes 

🛡️ Cybersecurity

Complete Study Notes for Government, Banking, SSC, UPSC, Railway & Other Competitive Exams

📚 62 MCQs with Answers 📊 All Important Tables 🇮🇳 Indian Laws & Initiatives ⚡ Quick Revision
62+
MCQs with Explanations
12
Topic Sections Covered
10+
Indian Govt Initiatives
🎯 1. What is Cybersecurity? — The CIA Triad

Cybersecurity is the practice of protecting computers, networks, programs, and data from unauthorized access, damage, or attacks.

C Confidentiality Only authorized people can access data
Example: Encrypting bank details
I Integrity Data is accurate & not tampered with
Example: Digital signatures
A Availability Systems accessible when needed
Example: No downtime in banks
Exam Tip: CIA Triad is the most frequently asked concept in Banking, SSC, Government & UPSC exams. A DDoS attack violates Availability. Data tampering violates Integrity. Eavesdropping violates Confidentiality.
🦠 2. Types of Malware (Malicious Software)
Malware TypeWhat It DoesKey Example
🔴 VirusAttaches to files; spreads when file is openedInfects .exe files
🪱 WormSelf-replicates across networks WITHOUT user actionILOVEYOU Worm (2000)
🐴 Trojan HorseDisguised as legitimate software; hides malwareFake antivirus programs
🔒 RansomwareEncrypts files; demands payment to unlockWannaCry (2017)
🕵️ SpywareSecretly monitors & steals user activityKeyloggers, banking trojans
📢 AdwareShows unwanted ads; may carry spywarePop-up advertising software
🫥 RootkitHides itself; gives attacker admin/root accessStealthy system backdoors
🤖 BotnetNetwork of infected computers controlled remotelyUsed in DDoS attacks
⌨️ KeyloggerRecords every keystroke (passwords, chats)Banking credential theft
💣 Logic BombMalicious code triggered at a specific time/eventActivates on a certain date
Exam Tip: Worm spreads automatically (no user action). Virus needs a host file. Trojan hides as legitimate software. Ransomware encrypts and demands ransom — WannaCry is the most exam-asked example.
🎣 3. Phishing & Social Engineering Attacks
Attack NameMethod / TargetMedium
PhishingFake emails to steal credentials from general users📧 Email
Spear PhishingTargeted phishing at a specific person or org📧 Email
WhalingPhishing targeting top executives — CEO, CFO, MD📧 Email
SmishingPhishing via fake SMS / text messages📱 SMS
VishingPhishing via fake phone calls (voice)📞 Phone
PretextingAttacker creates a fake story/scenario to extract infoAny
BaitingLeaving infected USB drives in public places🖥️ Physical
Quid Pro QuoOffering fake “help” in exchange for sensitive infoPhone/Online
TailgatingEntering restricted area by following authorized person🚪 Physical
Shoulder SurfingWatching someone type passwords in public👀 Physical
Memory Trick: Smishing = SMS | Vishing = Voice | Whaling = Wealthiest (CEOs) | Spear = Specific person
🌐 4. Network & Web Attacks
AttackWhat Happens
DoS (Denial of Service)Overloads server from one source → website goes down
DDoS (Distributed DoS)Same as DoS but from thousands of machines (botnet) — harder to block
MITM (Man-in-the-Middle)Attacker secretly intercepts & alters communication between two parties
SQL InjectionInjects malicious SQL code into database via web form inputs
XSS (Cross-Site Scripting)Injects malicious scripts into web pages viewed by other users
CSRFTricks logged-in users into performing unintended actions on a website
DNS SpoofingRedirects users to fake/malicious websites via DNS manipulation
Zero-Day ExploitAttacks a vulnerability before a patch exists — most dangerous
Brute ForceTrying all possible passwords until correct one is found
Rainbow Table AttackUses pre-computed hash values to crack passwords quickly
Drive-by DownloadMalware downloaded automatically just by visiting a website
Credential StuffingUses leaked credentials from one site to break into other sites
🛡️ 5. Cyber Defense Measures & Security Tools
Tool / ControlFull FormWhat It Does
FirewallBlocks/allows network traffic based on security rules
Antivirus / Anti-malwareDetects and removes malicious software
EncryptionConverts data to unreadable form; only authorized can decode
VPNVirtual Private NetworkCreates encrypted tunnel over public internet
IDSIntrusion Detection SystemDetects suspicious activity and alerts (does not block)
IPSIntrusion Prevention SystemDetects AND blocks threats in real-time
DLPData Loss PreventionPrevents unauthorized data transfer or leakage
SIEMSecurity Info & Event ManagementCollects, correlates & analyzes security logs
WAFWeb Application FirewallProtects web apps from SQL Injection, XSS etc.
EDREndpoint Detection & ResponseMonitors & responds to threats on individual devices
HoneypotDecoy system to attract & study attacker behavior
SOCSecurity Operations Center24/7 team monitoring security events & responding to incidents
MFAMulti-Factor AuthenticationPassword + OTP + Biometric = stronger login security
🔐 Access Control Models
ModelFull FormHow Access is Decided
DACDiscretionary Access ControlData owner decides who gets access
MACMandatory Access ControlSystem enforces access based on security labels
RBACRole-Based Access ControlAccess based on user’s job role — most common in exams
ABACAttribute-Based Access ControlAccess based on user attributes, time, location etc.
Exam Tip: IDS only detects. IPS detects + blocks. RBAC = access by role. Honeypot = decoy/trap for attackers.
🔑 6. Cryptography & Encryption
TypeKeys UsedSpeedExamplesUsed For
SymmetricSame key for encrypt & decrypt⚡ FastAES, DES, 3DESBulk data encryption
AsymmetricPublic key encrypts; Private key decrypts🐢 SlowerRSA, ECCKey exchange, digital signatures
HashingOne-way — cannot be decrypted⚡⚡ Very FastSHA-256, MD5Data integrity verification
TermWhat It Means / Why Important
AESAdvanced Encryption Standard — most widely used symmetric cipher today
RSAMost common asymmetric algorithm — used for key exchange & digital signatures
SHA-256Secure Hash Algorithm — used for data integrity. Output = 256-bit hash
MD5Outdated hash — vulnerable to collisions; do not use for security
SSL/TLSProtocols that secure internet connections → enable HTTPS
HTTPSHTTP over TLS — Port 443 — secure web browsing
Digital SignatureVerifies sender identity and document integrity using asymmetric keys
PKIPublic Key Infrastructure — system to manage digital certificates
CACertificate Authority — issues and verifies digital certificates
Exam Tip: AES = Symmetric (fast) | RSA = Asymmetric (key exchange) | HTTPS = Port 443 | MD5 = Weak/Deprecated | SHA-256 = Integrity
👤 7. Types of Hackers
Hacker TypeDescriptionLegal?
🤍 White HatEthical hackers who find & report vulnerabilities legallyLegal
🖤 Black HatCriminal hackers who exploit systems for personal gainIllegal
🩶 Grey HatHack without permission but may report flaws (not purely malicious)Unclear
👶 Script KiddieUse ready-made tools without deep technical knowledgeIllegal
✊ HacktivistHack for social/political causes (e.g., Anonymous group)Illegal
🏠 Insider ThreatEmployees/contractors who misuse their internal accessIllegal
🔴 Red HatAggressively fight black-hat hackers using offensive methodsVaries
🔵 Blue HatExternal security testers invited before a product launchLegal
🏛️ State-SponsoredGovernment-backed hackers targeting other nationsControversial
⚖️ 8. Indian Cybersecurity Laws
📜
Information Technology (IT) Act, 2000 — Main law governing cybercrime and electronic governance in India
SectionProvisionExam Priority
Sec 43Unauthorized access, downloading, copying or extracting dataHIGH
Sec 65Tampering with computer source codeMEDIUM
Sec 66Hacking & computer-related offencesHIGH
Sec 66ASending offensive messages online — struck down by Supreme Court in 2015 (Shreya Singhal case)HIGH
Sec 66CIdentity theft (including Aadhaar misuse)HIGH
Sec 66DOnline cheating / phishing using computerHIGH
Sec 66EViolation of privacy — capturing/publishing private imagesMEDIUM
Sec 66FCyber Terrorism — Punishment: Life ImprisonmentHIGH ⭐
Sec 67Publishing obscene material onlineMEDIUM
Sec 69AGovernment power to block websitesHIGH ⭐
Sec 70Protected Systems (critical infrastructure)MEDIUM
Sec 70BCERT-In designated as National Nodal AgencyHIGH ⭐
🆕
Digital Personal Data Protection Act (DPDPA), 2023 — India’s dedicated data privacy law
  • Data Principal = the individual whose data is collected
  • Data Fiduciary = entity that processes personal data
  • Consent required before processing personal data
  • Data Breach Reporting is mandatory to CERT-In
  • Right to erase data / right to correct inaccurate data
  • Penalties up to ₹250 crore for serious violations
Exam Tip: Section 66F = Cyber Terrorism (Life Imprisonment) | Section 69A = Block Websites | Section 70B = CERT-In as National Nodal Agency | Section 66A = STRUCK DOWN in 2015
🇮🇳 9. Indian Cybersecurity Organizations & Initiatives
📌 Key Organizations
OrganizationFull FormRole
CERT-InComputer Emergency Response Team – IndiaNational agency for cyber incident response; issues advisories (under MeitY)
NCIIPCNational Critical Information Infrastructure Protection CentreProtects critical sectors: power, banking, telecom, transport (under NTRO)
I4CIndian Cyber Crime Coordination CentreCoordinates response to cybercrime (under Ministry of Home Affairs)
DSCIData Security Council of IndiaIndustry body set up by NASSCOM for data protection practices
NICNational Informatics CentreProvides IT infrastructure to Government of India
NTRONational Technical Research OrganisationTechnical intelligence including the cyber domain
🚀 Key Schemes & Initiatives
InitiativeDetails
National Cyber Security Policy (NCSP) 2013India’s first comprehensive cyber protection policy
National Cyber Security Strategy 2020Updated strategy for strengthening India’s cyber ecosystem
Cyber Surakshit BharatMeitY initiative for cybersecurity awareness among govt officials
CyberDostMHA social media initiative for public cyber safety awareness
National Cybercrime Reporting Portalwww.cybercrime.gov.in — report online crimes here
Cybercrime Helpline1930 — national cybercrime helpline number
Digital IndiaBroad e-governance initiative with cyber safety as a component
🔔
Must Remember: Cybercrime Helpline = 1930 | Report at = cybercrime.gov.in | CERT-In under MeitY | NCIIPC under NTRO | I4C under MHA | DSCI founded by NASSCOM
📖 10. Important Cybersecurity Terms
TermSimple Definition
VulnerabilityA weakness in a system that can be exploited by an attacker
ThreatA potential source of harm to a system or network
RiskProbability that a threat will exploit a vulnerability (= Threat × Vulnerability)
ExploitA code or technique used to take advantage of a vulnerability
PatchA software update that fixes a known vulnerability
Zero-DayVulnerability unknown to the vendor; exploited before any patch exists
APTAdvanced Persistent Threat — long-term targeted attack by skilled adversaries
CVECommon Vulnerabilities and Exposures — standardized ID for known vulnerabilities
CVSSCommon Vulnerability Scoring System — scores vulnerability severity 0–10
BotnetNetwork of infected computers controlled remotely by an attacker
Dark WebHidden internet accessed via Tor browser; used for illegal activity
DeepfakeAI-generated fake video/audio used for fraud or misinformation
SteganographyHiding secret data inside ordinary files (images, audio)
SandboxIsolated environment to safely run and test suspicious code
Red TeamOffensive security team — simulates real attacker behavior
Blue TeamDefensive security team — protects against attacks
OSINTOpen Source Intelligence — gathering info from public sources
DMZDemilitarized Zone — buffer network between internet and internal systems
Firewall DMZArea where public-facing servers (web, mail) are placed, isolated from internal network
🌐 11. Important Ports, Standards & Emerging Trends
🔌 Important Port Numbers (Frequently Asked)
80
HTTP
TCP
443
HTTPS ⭐
Secure
22
SSH ⭐
Encrypted
21
FTP
Insecure
23
Telnet
Insecure
25
SMTP (Email)
TCP
53
DNS
UDP/TCP
110
POP3
Email
3389
RDP
Remote
📐 Key Frameworks & Standards
StandardWhat It Covers
ISO/IEC 27001International standard for Information Security Management Systems (ISMS)
NIST Framework5 steps: Identify → Protect → Detect → Respond → Recover
PCI DSSPayment Card Industry Data Security Standard — for card payment security
GDPREU’s General Data Protection Regulation — strongest data privacy law globally
🚀 Emerging Trends (High Exam Probability)

🤖 AI in Cybersecurity

  • AI used to create smarter malware & phishing
  • AI also used for threat detection & anomaly identification
  • Deepfakes powered by AI for fraud

🔒 Ransomware-as-a-Service

  • Cybercriminals rent ransomware tools to others
  • WannaCry (2017) infected 150+ countries
  • Regular backups = best defense

🔗 Supply Chain Attacks

  • Target software vendors to attack their clients
  • SolarWinds attack (2020) is the famous example
  • Affects thousands of organizations at once

🛡️ Zero Trust Security

  • “Never trust, always verify”
  • No implicit trust even inside the network
  • Verify every user, device, request
12. Quick Revision Cheat Sheet
CIA TriadConfidentiality · Integrity · Availability
Main Cyber LawIT Act, 2000
Cyber TerrorismIT Act Sec 66F → Life Imprisonment
Website BlockingIT Act Sec 69A
CERT-InSection 70B — National Nodal Agency (under MeitY)
Data Privacy LawDPDPA, 2023
Cybercrime Helpline📞 1930
Report Cybercrime🌐 cybercrime.gov.in
NCIIPCProtects critical infrastructure (under NTRO)
I4CCybercrime coordination (under MHA)
DSCI Founded byNASSCOM
NCSP First PolicyNational Cyber Security Policy — 2013
Symmetric EncryptionAES — same key, fast
Asymmetric EncryptionRSA — public + private keys
HTTPS Port443 ⭐ (HTTP = 80)
SSH Port22 (Telnet = 23, insecure)
Zero-DayNo patch exists yet — most dangerous
WannaCry (2017)Famous ransomware — 150+ countries
SolarWinds (2020)Famous supply chain attack
Sec 66A Struck DownShreya Singhal case — Supreme Court 2015
Phishing via SMSSmishing
Phishing via VoiceVishing
Phishing targeting CEOWhaling
Zero Trust Principle“Never trust, always verify”
NIST FrameworkIdentify → Protect → Detect → Respond → Recover
ISO/IEC 27001Global info security management standard
MD5Weak / Deprecated hash — avoid for security
IDS vs IPSIDS = Detect only | IPS = Detect + Block
White Hat HackerEthical hacker — legal
MFAMulti-Factor Authentication (most secure login)
📝 Practice MCQs — With Answers & Explanations
💡
62 questions organized by topic. Green options = correct answer. Read explanations to understand why — not just what.
🎯 Section A — CIA Triad & Basic Concepts
1What does “CIA” in the CIA Triad stand for?
  • A. Cyber Intelligence Agency
  • B. Confidentiality, Integrity, Availability
  • C. Control, Identification, Authentication
  • D. Cipher, Integrity, Access
✅ Answer: B The CIA Triad is the foundation of cybersecurity. Confidentiality = restrict access | Integrity = ensure accuracy | Availability = ensure access when needed.
2A DDoS attack that shuts down a website violates which CIA Triad principle?
  • A. Confidentiality
  • B. Integrity
  • C. Availability
  • D. Authentication
✅ Answer: C DDoS (Distributed Denial of Service) makes the website unavailable to legitimate users, directly violating the Availability principle.
3Which CIA Triad principle is violated when a hacker tampers with financial records?
  • A. Confidentiality
  • B. Integrity
  • C. Availability
  • D. Authenticity
✅ Answer: B Integrity ensures data is accurate and unmodified. Tampering with records violates integrity. Digital signatures and hashing protect integrity.
🦠 Section B — Malware & Attack Types
4Which malware encrypts user files and demands payment to restore access?
  • A. Spyware
  • B. Worm
  • C. Ransomware
  • D. Rootkit
✅ Answer: C Ransomware encrypts victim’s data and demands ransom (usually in cryptocurrency). WannaCry (2017) is the most famous example, affecting 150+ countries.
5Which malware spreads across networks automatically WITHOUT any user action?
  • A. Virus
  • B. Worm
  • C. Trojan
  • D. Adware
✅ Answer: B Worms self-replicate and spread automatically. Unlike viruses, they do NOT need to attach to a host file or require user action.
6The WannaCry cyberattack (2017) is an example of:
  • A. Spyware
  • B. DDoS Attack
  • C. Ransomware
  • D. SQL Injection
✅ Answer: C WannaCry was a global ransomware attack that exploited a Windows vulnerability (EternalBlue) and infected 200,000+ computers in 150 countries.
7Which attack involves an attacker secretly intercepting communication between two parties?
  • A. SQL Injection
  • B. DDoS Attack
  • C. Man-in-the-Middle (MITM)
  • D. Ransomware
✅ Answer: C In MITM attacks, the attacker inserts themselves between two communicating parties and can eavesdrop or alter messages without their knowledge.
8What is a Zero-Day vulnerability?
  • A. A vulnerability fixed within zero hours
  • B. A vulnerability that only affects old systems
  • C. An unknown vulnerability exploited before any patch exists
  • D. A flaw in zero-bit encryption
✅ Answer: C Zero-Day means the vendor has “zero days” to fix it — they may not even know it exists. These are extremely dangerous as no defense is available yet.
9A DDoS attack uses which of the following to flood a target with traffic?
  • A. A single laptop
  • B. A botnet (thousands of infected machines)
  • C. SQL queries
  • D. Phishing emails
✅ Answer: B DDoS = Distributed Denial of Service. It uses a botnet (network of compromised computers) to overwhelm a target from multiple sources simultaneously.
10Which attack injects malicious code into a website’s database through input fields?
  • A. CSRF Attack
  • B. XSS Attack
  • C. SQL Injection
  • D. MITM Attack
✅ Answer: C SQL Injection manipulates database queries through unsanitized user inputs in web forms. Parameterized queries / prepared statements prevent this attack.
🎣 Section C — Phishing & Social Engineering
11What is Phishing?
  • A. A network scanning technique
  • B. Sending fake emails to trick users into revealing credentials
  • C. A type of firewall
  • D. Encrypted communication protocol
✅ Answer: B Phishing uses deceptive emails that mimic legitimate organizations (banks, government) to steal login credentials or financial information.
12Phishing targeted specifically at CEO or CFO of an organization is called:
  • A. Spear Phishing
  • B. Whaling
  • C. Smishing
  • D. Vishing
✅ Answer: B Whaling targets the “big fish” — senior executives (CEO, CFO, Director). The term comes from targeting the largest targets, just like whale hunting.
13Which of the following is NOT a type of phishing?
  • A. Spear Phishing
  • B. Whaling
  • C. Smishing
  • D. Shimming
✅ Answer: D Shimming is a payment card fraud technique (tampers with chip cards) — it is NOT a phishing variant. The others are all phishing types.
14Phishing carried out via fake SMS messages is called:
  • A. Vishing
  • B. Smishing
  • C. Spear Phishing
  • D. Whaling
✅ Answer: B Smishing = SMS + Phishing. Attackers send fake text messages claiming to be from banks, TRAI, or government to steal information.
15An attacker leaves infected USB drives in a company’s parking lot. This social engineering technique is called:
  • A. Tailgating
  • B. Pretexting
  • C. Baiting
  • D. Vishing
✅ Answer: C Baiting exploits human curiosity. Infected USB drives are left in visible places hoping employees will plug them in, installing malware automatically.
⚖️ Section D — Indian Cybersecurity Laws
16Which Indian law primarily deals with cybercrime and electronic governance?
  • A. IT Act, 2000
  • B. Indian Penal Code, 1860
  • C. Evidence Act, 1872
  • D. Companies Act, 2013
✅ Answer: A The Information Technology Act, 2000 is the primary legislation governing cybercrime, electronic commerce, and digital signatures in India.
17Which section of the IT Act deals with Cyber Terrorism?
  • A. Section 43
  • B. Section 66D
  • C. Section 66F
  • D. Section 69A
✅ Answer: C Section 66F covers Cyber Terrorism with punishment up to Life Imprisonment. It is one of the most serious provisions in the IT Act.
18Which section of the IT Act empowers the government to block websites?
  • A. Section 43
  • B. Section 66C
  • C. Section 70B
  • D. Section 69A
✅ Answer: D Section 69A empowers the government to block online content/websites in the interest of national security, public order, or decency.
19Section 70B of the IT Act designates which organization as the National Nodal Agency?
  • A. NIC
  • B. NCIIPC
  • C. CERT-In
  • D. I4C
✅ Answer: C CERT-In (Computer Emergency Response Team – India) is designated as the National Nodal Agency under Section 70B of the IT Act, 2000.
20Which IT Act section was struck down by the Supreme Court in 2015 for violating freedom of speech?
  • A. Section 66
  • B. Section 66A
  • C. Section 66C
  • D. Section 70B
✅ Answer: B In the landmark Shreya Singhal vs Union of India (2015) case, the Supreme Court struck down Section 66A (offensive online messages) as unconstitutional for violating Article 19(1)(a).
21India’s dedicated data privacy legislation enacted in 2023 is:
  • A. IT Act 2000 Amendment
  • B. Privacy Protection Act 2023
  • C. Digital Personal Data Protection Act (DPDPA), 2023
  • D. National Data Governance Framework
✅ Answer: C The DPDPA 2023 is India’s comprehensive data protection legislation governing how personal data is collected, stored, and processed, with penalties up to ₹250 crore.
22Which IT Act section covers Online Cheating / Phishing?
  • A. Section 65
  • B. Section 66C
  • C. Section 66D
  • D. Section 69A
✅ Answer: C Section 66D covers cheating by impersonation using computer resources — directly applicable to phishing and online fraud.
🇮🇳 Section E — Indian Organizations & Initiatives
23What is CERT-In?
  • A. A banking sector regulator
  • B. Computer Emergency Response Team – India, the national cybersecurity incident response agency
  • C. A data encryption standard for India
  • D. A certification exam for ethical hackers
✅ Answer: B CERT-In handles cyber incident response, issues security advisories, and coordinates India’s national cybersecurity. It functions under MeitY.
24What is the national cybercrime helpline number in India?
  • A. 112
  • B. 1930
  • C. 100
  • D. 155260
✅ Answer: B 1930 is the dedicated national cybercrime helpline. Victims can report incidents at cybercrime.gov.in. This is frequently asked in banking and government exams.
25NCIIPC is responsible for:
  • A. Issuing cybercrime FIRs
  • B. Managing UIDAI Aadhaar data
  • C. Protecting India’s critical information infrastructure (power, banking, telecom)
  • D. Providing internet to rural areas
✅ Answer: C NCIIPC (National Critical Information Infrastructure Protection Centre), under NTRO, protects India’s critical sectors — power grids, financial systems, telecommunications, and transport.
26I4C stands for:
  • A. Indian Internet Infrastructure & Communication Centre
  • B. Indian Cyber Crime Coordination Centre
  • C. International Information & Cyber Coordination Centre
  • D. Indian Identity & Credential Control Centre
✅ Answer: B I4C (Indian Cyber Crime Coordination Centre) was established by the Ministry of Home Affairs to coordinate India’s fight against cybercrime.
27CERT-In operates under which ministry?
  • A. Ministry of Home Affairs
  • B. Ministry of Finance
  • C. Ministry of Electronics and Information Technology (MeitY)
  • D. Ministry of Defence
✅ Answer: C CERT-In is under MeitY. In contrast, I4C is under MHA (Ministry of Home Affairs).
28India’s first National Cyber Security Policy was launched in:
  • A. 2000
  • B. 2008
  • C. 2013
  • D. 2020
✅ Answer: C India’s first National Cyber Security Policy (NCSP) was launched in 2013, focusing on creating a safe, secure, and resilient cyberspace for India.
29DSCI (Data Security Council of India) was set up by:
  • A. Government of India
  • B. RBI
  • C. NASSCOM
  • D. CERT-In
✅ Answer: C DSCI is an industry body set up by NASSCOM (India’s IT industry association) to promote data protection and cybersecurity practices.
🔐 Section F — Encryption & Network Security
30Which of the following is a Symmetric Encryption algorithm?
  • A. RSA
  • B. ECC
  • C. AES
  • D. Diffie-Hellman
✅ Answer: C AES (Advanced Encryption Standard) is symmetric — the same key is used for both encryption and decryption. RSA and ECC are asymmetric algorithms.
31HTTPS uses which default port number?
  • A. 80
  • B. 21
  • C. 25
  • D. 443
✅ Answer: D HTTPS (HTTP over TLS/SSL) uses Port 443. Plain HTTP uses Port 80. This is one of the most frequently asked port numbers in exams.
32Which hashing algorithm is considered weak and deprecated for security use?
  • A. SHA-256
  • B. SHA-512
  • C. MD5
  • D. SHA-3
✅ Answer: C MD5 is cryptographically broken — two different inputs can produce the same hash (collision). It should not be used for security purposes today.
33Which protocol provides secure, encrypted remote access to servers?
  • A. FTP (Port 21)
  • B. Telnet (Port 23)
  • C. SSH (Port 22)
  • D. HTTP (Port 80)
✅ Answer: C SSH (Secure Shell) on Port 22 provides encrypted remote access. Telnet (Port 23) is insecure as it transmits data in plain text.
34What is the primary purpose of a Digital Signature?
  • A. To encrypt large files quickly
  • B. To verify the sender’s identity and ensure document integrity
  • C. To create strong passwords
  • D. To block network intrusions
✅ Answer: B A Digital Signature uses asymmetric cryptography to verify that a document was sent by a specific party and has not been altered in transit.
🛡️ Section G — Defense Measures & Security Tools
35What is the primary function of a Firewall?
  • A. Encrypt data stored on disk
  • B. Monitor and filter network traffic based on security rules
  • C. Detect application software bugs
  • D. Automatically backup data
✅ Answer: B A firewall examines incoming and outgoing network packets and blocks or allows them based on predefined security rules.
36What is the key difference between IDS and IPS?
  • A. IDS blocks threats; IPS only detects them
  • B. Both are exactly the same
  • C. IDS only detects and alerts; IPS detects AND blocks threats
  • D. IPS is older; IDS is newer
✅ Answer: C IDS = Intrusion Detection System (alerts only). IPS = Intrusion Prevention System (detects + blocks in real-time).
37A Honeypot in cybersecurity is:
  • A. A secure encrypted database
  • B. A decoy system designed to attract, trap, and study attackers
  • C. A type of firewall configuration
  • D. An encrypted USB storage device
✅ Answer: B Honeypots are intentionally vulnerable fake systems. When attackers interact with them, security teams gather intelligence about attack methods and techniques.
38MFA (Multi-Factor Authentication) uses:
  • A. Password only
  • B. OTP only
  • C. Two or more authentication factors from different categories
  • D. Biometrics only
✅ Answer: C MFA combines: Something you KNOW (password) + Something you HAVE (OTP/token) + Something you ARE (biometric). Any two or more from different categories.
39The principle of Least Privilege means:
  • A. Give all employees administrator rights
  • B. Users get only the minimum access required for their job
  • C. Only senior managers can access the network
  • D. Use the weakest encryption possible
✅ Answer: B Least Privilege limits damage if an account is compromised by ensuring users can only access what they absolutely need for their specific role.
40RBAC stands for:
  • A. Risk-Based Access Control
  • B. Role-Based Access Control
  • C. Remote Backup Access Control
  • D. Regulated Browser Access Control
✅ Answer: B RBAC assigns access permissions based on a user’s role. Example: A bank teller has different system access than a branch manager or IT administrator.
41VPN primarily provides:
  • A. Faster internet connection
  • B. A secure, encrypted tunnel over public networks
  • C. Built-in antivirus protection
  • D. Automatic website blocking
✅ Answer: B VPN (Virtual Private Network) creates an encrypted connection over the internet, masking user’s IP address and protecting data from interception.
📐 Section H — Frameworks & Standards
42Which global framework is the international standard for Information Security Management?
  • A. PCI DSS
  • B. GDPR
  • C. ISO/IEC 27001
  • D. HIPAA
✅ Answer: C ISO/IEC 27001 is the globally recognized standard for establishing and maintaining an Information Security Management System (ISMS).
43The NIST Cybersecurity Framework’s five core functions are:
  • A. Plan, Do, Check, Act, Review
  • B. Identify, Protect, Detect, Respond, Recover
  • C. Assess, Monitor, Control, Report, Improve
  • D. Prevent, Detect, Contain, Recover, Learn
✅ Answer: B NIST CSF: Identify (assets/risks) → Protect (safeguards) → Detect (anomalies) → Respond (incidents) → Recover (restore services).
44PCI DSS applies to organizations that:
  • A. Manage government databases
  • B. Store health records
  • C. Process or store payment card data
  • D. Operate electoral databases
✅ Answer: C PCI DSS (Payment Card Industry Data Security Standard) sets mandatory security requirements for all organizations that handle credit/debit card transactions.
🚀 Section I — Emerging Trends & Advanced Topics
45The SolarWinds cyberattack (2020) is a famous example of:
  • A. DDoS Attack
  • B. Phishing Attack
  • C. Supply Chain Attack
  • D. SQL Injection
✅ Answer: C In the SolarWinds attack, hackers compromised a legitimate software update to reach thousands of government and corporate clients — a textbook supply chain attack.
46Zero Trust Security is based on which principle?
  • A. Trust all users inside the network
  • B. Trust but verify
  • C. Never trust, always verify
  • D. Trust after a single successful login
✅ Answer: C Zero Trust assumes no user or device is inherently trustworthy — even inside the network. Every access request must be verified regardless of location.
47Ransomware-as-a-Service (RaaS) means:
  • A. Government agencies providing ransomware tools for research
  • B. Antivirus companies selling ransomware protection subscriptions
  • C. Cybercriminals selling/renting ransomware tools to other criminals
  • D. Banks providing financial insurance against ransomware attacks
✅ Answer: C RaaS is a criminal business model where ransomware developers lease their tools to affiliates who carry out attacks and share ransom profits.
48Which technology may potentially break current encryption standards like RSA in the future?
  • A. Blockchain
  • B. 5G Networks
  • C. Quantum Computing
  • D. Augmented Reality
✅ Answer: C Quantum computers could use algorithms like Shor’s algorithm to crack RSA encryption. This is why Post-Quantum Cryptography (PQC) is being developed as a defense.
49Deepfake technology is primarily a threat because:
  • A. It disrupts network traffic
  • B. It causes database breaches
  • C. It enables identity fraud and disinformation using AI-generated fake media
  • D. It physically damages computer hardware
✅ Answer: C Deepfakes use AI to create highly convincing fake videos/audio of real people, enabling fraud, blackmail, and spreading of false information.
🔍 Section J — Important Definitions & Miscellaneous
50What is Digital Forensics?
  • A. Creating digital signatures for documents
  • B. Investigating cyber incidents and preserving digital evidence for legal use
  • C. Encrypting digital files securely
  • D. Automatically creating data backups
✅ Answer: B Digital forensics recovers and analyzes data from digital devices to investigate crimes and preserve evidence in a legally admissible manner (chain of custody).
51CVE stands for:
  • A. Cyber Vulnerability Event
  • B. Critical Vulnerability Exchange
  • C. Common Vulnerabilities and Exposures
  • D. Classified Vulnerability Entry
✅ Answer: C CVE is a public database of known cybersecurity vulnerabilities. Each gets a unique ID (e.g., CVE-2021-44228 for Log4Shell). CVSS scores their severity from 0–10.
52The Dark Web is accessed using:
  • A. Google Chrome with a VPN
  • B. Tor Browser (The Onion Router)
  • C. Microsoft Edge in InPrivate mode
  • D. Firefox with extensions
✅ Answer: B The Dark Web requires Tor (The Onion Router) browser, which routes traffic through multiple encrypted relays to anonymize users.
53An APT (Advanced Persistent Threat) is characterized by:
  • A. Quick, random attacks on multiple targets
  • B. Long-term, targeted attacks by skilled adversaries (often nation-state actors)
  • C. Simple brute-force password attacks
  • D. Automated virus spreading
✅ Answer: B APTs are sophisticated, stealthy, long-duration attacks targeting specific high-value organizations for espionage or data theft, often backed by governments.
54Steganography is:
  • A. A type of ransomware attack
  • B. Hiding secret data inside ordinary files like images or audio
  • C. A network scanning technique
  • D. A form of asymmetric encryption
✅ Answer: B Steganography conceals the existence of a secret message by embedding it inside another file. Unlike encryption (hides content), steganography hides the fact that a message exists.
55Shoulder Surfing is:
  • A. A network-layer attack
  • B. Watching someone type passwords or PINs in public places
  • C. An attack via compromised Wi-Fi networks
  • D. A type of social media hacking
✅ Answer: B Shoulder surfing is a physical social engineering technique where attackers observe victims entering PINs at ATMs, typing passwords, or viewing sensitive screens.
56SIEM is used to:
  • A. Encrypt email messages
  • B. Block network traffic at the firewall
  • C. Collect, correlate, and analyze security logs from multiple sources
  • D. Automatically patch software vulnerabilities
✅ Answer: C SIEM (Security Information and Event Management) aggregates logs from servers, firewalls, and applications, providing real-time threat detection and compliance reporting.
57Which of the following is the best practice for storing user passwords?
  • A. Store in plain text for easy recovery
  • B. Encode with Base64
  • C. Encrypt with AES only
  • D. Use salted hashing (e.g., bcrypt or Argon2)
✅ Answer: D Salted hashing adds random data before hashing, preventing rainbow table attacks. bcrypt and Argon2 are designed to be slow, making brute-force attacks computationally expensive.
58Patch Management refers to:
  • A. Hiring contractors to physically repair servers
  • B. Regularly applying software updates/fixes to close security vulnerabilities
  • C. Encrypting data at rest
  • D. Installing antivirus software once
✅ Answer: B Patch management is the systematic process of identifying, testing, and applying software patches (updates) to fix known vulnerabilities before attackers can exploit them.
59Which of the following best describes Social Engineering?
  • A. Hacking social media platforms
  • B. Manipulating people psychologically to reveal sensitive information or perform actions
  • C. Engineering social networks for maximum engagement
  • D. A cryptographic technique for social data
✅ Answer: B Social Engineering exploits human psychology rather than technical vulnerabilities. Phishing, pretexting, baiting, and tailgating are all social engineering techniques.
60Which of the following is an example of Biometric Authentication?
  • A. Password + OTP combination
  • B. Smart card inserted into a reader
  • C. Fingerprint scan or face recognition
  • D. Security question answer
✅ Answer: C Biometrics use physical characteristics — fingerprint, face, iris, voice — falling in the “something you are” authentication category. It is the strongest form of single-factor authentication.
61Which cloud security model states that security is a shared responsibility between the cloud provider and the customer?
  • A. Cloud providers are always fully responsible for security
  • B. Customers are responsible only for physical infrastructure
  • C. Shared Responsibility Model — both provider and customer have defined security roles
  • D. No security is required in cloud environments
✅ Answer: C The Shared Responsibility Model means cloud providers secure the infrastructure (hardware, network) while customers are responsible for their data, applications, and access management.
62The WannaCry ransomware attack occurred in which year?
  • A. 2015
  • B. 2016
  • C. 2017
  • D. 2019
✅ Answer: C WannaCry struck in May 2017, exploiting a Windows vulnerability (EternalBlue) and affecting 200,000+ computers in 150+ countries, including hospitals, banks, and telecom companies.