Cybersecurity Fundamentals Interview Questions and Answers for 2025 – Beginner to Advanced

The practice of protecting systems, networks, and programs from digital attacks.

It safeguards privacy, prevents financial loss, and ensures business continuity.

A security barrier that controls incoming and outgoing traffic based on security rules.

A type of attack where attackers pose as trusted entities to steal sensitive data.

Converting data into a secure format to prevent unauthorized access.

Confidentiality, Integrity, and Availability—core principles of cybersecurity.

Malicious software intended to harm devices or steal information.

A Virtual Private Network encrypts internet traffic for secure remote access.

Phishing emails that trick users into sharing credentials.

Strong passwords, 2FA, regular updates, data backups.

A malware that encrypts files and demands payment for decryption.

Black hat hackers exploit systems maliciously, while white hat hackers use similar skills ethically to find and fix vulnerabilities.

Symmetric uses one key for encryption/decryption; asymmetric uses a public-private key pair for secure communication without sharing private keys.

IDS detects unauthorized access but doesn’t block it; IPS detects and can block threats in real-time.

SQL injection exploits vulnerabilities by injecting malicious SQL statements. Prevention includes parameterized queries, input validation, and least privilege access.

An attacker intercepts communication to steal or alter information. Prevention includes encryption, HTTPS, VPNs, and certificate pinning.

Process of regularly updating software to fix security vulnerabilities, bugs, and improve functionality.

Encoding transforms data into a different format for compatibility; encryption protects data confidentiality; hashing creates fixed-size unique values for verification.

A centralized unit that monitors, detects, and responds to cybersecurity incidents.

Collection and analysis of data about existing or potential cyber threats to proactively defend systems.

Users or systems are granted the minimum access necessary to perform tasks, reducing attack surfaces.

Public Wi-Fi can expose users to eavesdropping, MITM attacks, malware spreading, and unsecured data transmission.

A security professional who tests systems for vulnerabilities with permission to strengthen defenses.

Measures to secure individual devices like computers, smartphones, and tablets from threats.

Methods like data shredding, overwriting, or physical destruction to prevent data recovery after disposal.

Authentication requiring two or more verification factors to increase security beyond passwords.

Manipulating people into divulging confidential information, rather than hacking technical systems directly.

A security flaw unknown to the software vendor, exploited by attackers before a fix is available.

Simulated cyber attack authorized to identify vulnerabilities and test security readiness.

Attack aiming to make a system or network unavailable to users by overwhelming it with traffic or exploiting vulnerabilities.

Functions producing fixed-size output from input data, used for data integrity and digital signatures. Examples include SHA-2 and SHA-3.

IDS monitors and alerts suspicious activities, whereas IPS also blocks or prevents those threats automatically.

An attack where valid data transmissions are maliciously or fraudulently repeated or delayed to gain unauthorized access.

A framework managing digital certificates and public-key encryption to enable secure communication and authentication.

Long-term, targeted cyberattacks where intruders maintain continuous access to a network to steal data or cause harm.

Isolating running programs in a restricted environment to prevent them from affecting the host system or accessing unauthorized resources.

Processes to securely generate, distribute, store, rotate, and revoke cryptographic keys to maintain data security.

Symmetric key algorithms (AES, DES), asymmetric key algorithms (RSA, ECC), and hashing algorithms (SHA, MD5).

A large number of compromised computers flood a target system with traffic, overwhelming resources and causing downtime.

Proactive search for cyber threats that evade automated security systems, using data analytics and intuition.

Identifying, evaluating, and prioritizing risks to assets and taking steps to mitigate or control them.

Digital tokens used to authenticate and authorize access, such as JWT tokens in web applications.

Blockchain security relies on cryptographic hashing, decentralization, immutability, and consensus mechanisms to protect data integrity.

A European privacy regulation mandating data protection and breach notification, influencing global security compliance practices.

Implement authentication, authorization, HTTPS, input validation, rate limiting, and logging.

Using multiple layers of security controls to provide redundancy and improve protection against attacks.

Controlled tests to train users against phishing attacks by sending simulated phishing emails.

Security Information and Event Management systems aggregate, analyze, and alert on security events.

Processes for identifying, evaluating, treating, and reporting security vulnerabilities.

Protocols like WPA2 and WPA3 encrypt wireless data to prevent eavesdropping and ensure confidentiality.

CISSP, CEH, CISA, CompTIA Security+, OSCP, among others.