Job opportunities for cybersecurity engineers are growing rapidly. Especially in 2025, the cybersecurity market is expected to reach $203 billion. There are over 3.5 million unfilled positions globally by the end of 2025, although there is expected growth of 33% in the industry. 

With such a rapid increase in demand for cybersecurity professionals, there is indeed high competition when it comes to hiring a cybersecurity engineer. Whether you’re a fresher or experienced cybersecurity engineer, this guide of cybersecurity interview questions is for you.

Before we begin, sharing a quote from an American computer science researcher:

"The only system which is truly secure is one which is switched off and unplugged, locked in a titanium safe, buried in a concrete bunker, and surrounded by nerve gas and very highly paid armed guards. Even then, I wouldn't stake my life on it." - Gene Spafford

Cyber Security Interview Questions for Freshers

1. Explain the difference between a threat, vulnerability and risk?

There are significant differences between the three of them. These are explained as follows:

• Vulnerability:

It represents a weakness in the system that can be exploited such as weak passwords or unpatched software.

• Threat:

It is a potential danger that can exploit a vulnerability like malicious hackers or malware.

• Risk:

It refers to the potential impact and likelihood of a threat exploiting a vulnerability. It is calculated as follows:

Risk = Threat × Vulnerability × Impact

2. Mention some of the common cyberattacks.

Some of the most common cyberattacks are as follows:

• Phishing: Phishing refers to the deceptive act of sending junk emails by pretending to be authentic sources.

• Social Engineering Attacks: Social engineering attacks may take numerous forms and may be performed anywhere human cooperation is needed.

• Ransomware: Ransomware is reported cryptography programming that employs unique cryptographic computations to encrypt documents within a targeted environment.

• Cryptocurrency Hijacking: With more use and popularity of digital money and mining, so too are cybercriminals. They have discovered an ugly benefit of cryptocurrency mining, which includes making difficult mathematical calculations to mine virtual money like Bitcoin, Ethereum, Monreo, and Litecoin.

• Botnet Attacks: Botnet attacks frequently hit big companies and organizations that acquire huge volumes of data. The attack enables programmers to command millions of devices in return for clever purposes.

3. What is meant by a Brute Force attack? How to prevent it?

The Brute Force attack uses a trial and error method. It is used to decode encrypted data. For example, trying to decode a password by trying various combinations of possible credentials. 

These brute force attacks are usually automated. Some of the ways you can avoid these cyberattacks are by making password complexity and length mandatory (and making sure that no one in the firm still uses a default password), implementing a two-factor authorization system, or limiting failed login attempts.

4. What is meant by cryptography? 

Cryptography in cybersecurity is the practice and science of methods for secure communication in the presence of opponents. It's fundamentally about making normal, readable information (plaintext) unreadable gibberish (ciphertext) and reversing the process.

Important features of cryptography in cybersecurity are as follows:

1. Protection of Data: Cryptography keeps information confidential by making it unreadable by unauthorized parties.

2. Main Functions:

• Encryption: Making plaintext into ciphertext with algorithms and keys

• Decryption: Converting ciphertext into plaintext using the right keys

• Hashing: Generating fixed-length representations of data that cannot be turned back

• Digital Signatures: Ensuring authenticity and integrity of messages

3. Key Types of Cryptography:

• Symmetric encryption: Employing the same key to encrypt and decrypt (AES, DES)

• Asymmetric encryption: Employing different keys to encrypt and decrypt (RSA, ECC)

• Hash functions: Producing fixed-size outputs for variable inputs (SHA-256, MD5)

4. Applications in Security:

• Securing communications (HTTPS, SSL/TLS)

• Protecting stored data (disk encryption)

• Authentication mechanisms (password hashing)

• Digital certificates and PKI (Public Key Infrastructure)

• Secure key exchange protocols (Diffie-Hellman)

5. What are the different sources of malware?

Various sources of malware are mentioned as follows:

• Spyware: Spyware is actually a kind of malicious software that operates in the background of your computer, steals all your personal data, and sends this information to remote attackers.

• Ransomware: Ransomware is utilized as malware to blackmail users into paying money as ransom by achieving unauthorized access to user confidential information and seeking payment in exchange for erasure or retrieval of that information from the user.

• Virus: Virus is a category of harmful malware that arrives as an attachment with a program or file. Viruses tend to propagate from a program to another program, and they will execute only when the host file is executed. The virus can harm the computer only until the host file is executed.

• Trojan: Trojans are non-replicating malicious malware that frequently makes the performance and efficiency of a computer deteriorate. Trojans can leak confidential user data and edit and erase this information.

• Adware: Adware is a form of malware that monitors the use of different forms of programs and files on your system and provides personalized ad suggestions depending on your history of use.

• Worms: A worm is essentially a form of malicious malware that replicates itself at a high speed from one system to another through email and file sharing. Worms don't need host software or code to run.

6. What is meant by XSS? How to prevent it?

Cross-site scripting is the full-form of XSS. It is a web security flaw that allows an attacker to manipulate how users interact with a susceptible application. It allows an attacker to get around the same-origin policy, which is meant to keep websites separate from one another. 

Cross-site scripting flaws allow an attacker to impersonate a victim user and execute any actions that the user is capable of, as well as access any of the user's data. If the victim user has privileged access to the application, the attacker may be able to take complete control of the app's functionality and data.

Preventing cross-site scripting may be easy in some situations but extremely hard in others, depending on the sophistication of the application and how it processes user-controllable data. As a whole, preventing XSS vulnerabilities will most likely require a combination of the following:

• Input Validation

• Validate all user input on the server side

• Use strict type checking and pattern matching

• Reject non-conforming inputs

• Output Encoding

• HTML-encode all dynamic content prior to rendering in browsers

• Use context-specific encoding (HTML, JavaScript, CSS, URL, etc.)

• Use built-in encoding libraries in your framework

• Content Security Policy (CSP)

• Enforce strong CSP headers to limit script sources

• Use 'nonce' or 'hash' values for inline scripts when needed

• Set 'unsafe-inline' and 'unsafe-eval' to false

• Use Framework Protections

• Take advantage of XSS protections in new frameworks

• Implement template engines which escape output automatically

• Update frameworks and libraries to current versions

• HTTP-only Cookies

• Make sensitive cookies HTTP-only to block JavaScript access

• Include the 'Secure' flag to send cookies only over HTTPS

• X-XSS-Protection Header

• Enable the X-XSS-Protection header to enable browser protection

• Set it to "1; mode=block" to block rendering of page in case of an attack

• Sanitize HTML

• Sanitize HTML using libraries when rich text is permitted

• Strip potentially harmful tags and attributes (script, onclick, etc.)

• Use CORS Correctly

• Enforce proper Cross-Origin Resource Sharing policies

• Don't use wildcards (*) in CORS configurations

• Avoid Manipulation of DOM with User Data

• Under no circumstances use inner HTML with user data

• Use text Content or create Text Node in place of inner HTML wherever possible

• Regular Security Tests

• Automated and manual security testing should be performed

• Code reviews should be regularly performed with a focus on XSS vulnerabilities

• Apply dynamic and static analysis tools to detect possible problems

7. Mention the difference between hashing and encryption.

8. What is the difference between HTTPS and SSL?

9. What is Meant by Black Hat, White Hat and Grey Hat Hackers?

Black Hat Hackers:

Black Hat hackers, more commonly referred to as crackers, try to get unauthorized entry into a system to sabotage its function or steal valuable information.

Due to its harmful intent, black hat hacking is always illegal, such as stealing business information, invading privacy, damaging systems, and denying network connection, among others.

White Hat Hackers:

Ethical hackers are also known as White hat hackers. In the process of penetration testing and vulnerability testing, they never want to do any damage to a system; instead, they want to find loopholes in a computer or network system.

Ethical hacking is legal and is one of the toughest jobs in the IT industry. Companies employ ethical hackers to perform penetration tests and vulnerability assessments.

Grey Hat Hackers:

Grey hat hackers take on characteristics of both black and white hat hacking. They do not do it with ill will, but as a matter of entertainment, they take advantage of an insecurity in a computer system or network without the owner's knowledge or consent.

Their intention is to make the owners aware of the defect in the expectation of receiving thankfulness or a little reward.

10.   What is a man-in-the-middle attack?

• A cyber attack (a form of eavesdropping attack) where a cybercriminal taps into a communication or data exchange between two individuals is referred to as a man-in-the-middle attack. 

• After a cybercriminal has entered a two-way discussion, they are perceived as legitimate participants, enabling them to gain sensitive information and react in multiple ways. 

• The primary intention behind this kind of attack is to obtain access to our business's or customers' personal data. 

• On an unsecured Wi-Fi network, for instance, a cybercriminal is able to intercept information being transmitted between the target machine and the network.

Scenario-Based Cyber Security Interview Questions 

Scenario 1: Incident Response to a Ransomware Attack

Question: 

Your company's critical servers have been hit by ransomware. Multiple systems are encrypted, and operations are impacted. As the cybersecurity lead, walk me through your immediate response steps and priorities.

Answer:

My initial response would adhere to a formal incident response plan:

1. Containment: I would isolate infected systems immediately by isolating them from the network to stop lateral movement. This involves physically disconnecting network cables if need be and blocking corresponding IP addresses at the firewall level.

2. Assessment and Evidence Collection: Prior to any remediation, I would determine the ransomware family by analyzing ransom notes and file extensions and retain digital evidence such as system logs, memory dumps, and encrypted file samples to analyze later through forensics.

3. Communication and Notification: I would engage the incident response team and set open communication channels. I would inform executive leadership, legal counsel, and ideally law enforcement based on severity. In cases involving regulated data, I would prep for compliance notifications (GDPR, HIPAA, etc.).

4. Business Continuity: I would initiate our business continuity plan, moving critical operations to clean systems or backup facilities if available, and recover most business-critical systems as prioritized based on our previously determined RTOs (Recovery Time Objectives).

5. Recovery Strategy: Instead of paying the ransom (which I would not recommend in general), I would initiate a recovery procedure utilizing our offline backups after we have verified they are not compromised. At the same time, I would start root cause analysis to discover and correct the original infection vector.

After recovery, I would conduct an exhaustive post-incident review to refresh our defenses and enhance our incident response for future occurrences.

Scenario 2: Identifying and Responding to a Data Exfiltration Attempt

Question: 

Your network monitoring system has detected unusual outbound traffic from a server containing sensitive customer data. The traffic is going to an unknown IP address during off-hours. How would you investigate and respond to this potential data exfiltration?

Answer:

I would address this possible data exfiltration with a systematic investigation and reaction:

1. Immediate Monitoring and Collection: I would increase monitoring on the suspicious server maintaining its existing state. I'd gather relevant logs (network, security, application), capture packet information, and create a timeline of activity without tip-offing possible attackers through making such obvious changes.

2. Traffic Analysis: I'd examine the suspect traffic behaviors to identify what data is being sent, how much, and the protocol it utilizes. I'd research the destination IP address using threat intelligence platforms to see if it's been linked to known command and control servers or malicious entities.

3. System Analysis: Without bringing the system down (which might notify an attacker), I would perform memory analysis and verify for unauthorized processes, suspicious scheduled tasks, changed system files, and unauthorized accounts. I'd search for persistence vectors such as registry changes or unauthorized services.

4. Controlled Response: Once I have enough evidence, I would execute a focused response: isolating the infected server from sensitive information while keeping the connection intact to keep watching the attack, installing additional monitoring to detect possible lateral movement, and having clean system images ready to recover.

5. Remediation and Prevention: Once we understand the attack vector in its entirety, I would create and execute an extensive remediation strategy: uninstalling malware/backdoors, patching weaknesses, updating access controls, reinforcing network segmentation, and deploying other data loss prevention controls specifically geared towards techniques utilized in this attack.

Along the way, I would have impeccable documentation for possible legal trials and communicate well with stakeholders in accordance with our incident response plan.

Scenario 3: Addressing Vulnerabilities in a Web Application

Question: 

Your security team has discovered several critical vulnerabilities in your company's customer-facing web application, including SQL injection and cross-site scripting (XSS) flaws. The development team says they need a month to fix these issues properly, but your CISO wants immediate action. How would you handle this situation?

Answer:

I would introduce a defense-in-depth strategy that harmonizes urgent security requirements with development constraints:

1. Risk Assessment and Prioritization: I would initially collaborate with the security team to assign numerical metrics to the actual risk exposure posed by each vulnerability, taking into consideration the exploitability of the vulnerability, the potential effect, and whether or not the vulnerabilities are currently being actively exploited. This aids in prioritizing response and justifying decisions to stakeholders.

2. Implement Temporary Mitigating Controls: Instead of holding out for full code remediations, I would install compensating controls like installing a Web Application Firewall (WAF) with rules that are designed against the found SQL injection and XSS patterns. I would further utilize virtual patching on the network and introduce stronger input validation at edge services.

3. Staged Remediation Plan: I would work with the development team to segment the fix into priority phases instead of viewing it as one month-long effort. High-priority vulnerabilities might even be solved by applying focused hotfixes in increments, closing the exposure window until the full solution is being constructed.

4. Improved Monitoring and Tripwires: As part of the fixes, I would put in place improved monitoring specifically searching for attempts at exploiting the known vulnerabilities, with automated notification of suspicious behavior and potentially honeypots to identify actively attacking attackers.

5. Stakeholder Management: I would submit an overall plan to the CISO indicating both the near-term mitigating controls and remediation timeline with defined milestones. I would assure open communication regarding residual risk throughout the remediation cycle and furnish daily status reports on both temporary remedies and permanent fix progress.

This methodology accepts the technical debt but simultaneously takes rapid steps to safeguard customers and the business, finding a balance between security and operational necessity.

Scenario 4: Responding to a Potential Insider Threat

Question: 

You've received an alert that a user with administrative privileges has been accessing sensitive financial databases outside of business hours and downloading unusually large amounts of data over the past week. This employee works in IT but has no business need to access financial data. How would you investigate and handle this potential insider threat?

Answer:

I would manage this sensitive insider threat situation with a careful balance of diligence and discretion:

1. Preliminary Validation: Before treating this as an incident, I would validate the alert to ensure it's not a false positive by cross-referencing the access logs with authorized maintenance windows, change management records, and any special projects that might explain the unusual access. I would verify account usage to ensure it wasn't compromised rather than actual insider activity.

2. Evidence Collection and Documentation: Upon confirming suspicious activity, I would quietly begin collecting and preserving evidence including access logs, download records, and database queries executed. I would document access patterns, timing, specific data accessed, and any attempts to cover tracks or circumvent controls, being careful to maintain a proper chain of custody for all evidence.

3. Collaborative Investigation: I would involve the minimum necessary stakeholders at this stage - typically HR, legal counsel, and perhaps a senior IT manager - while maintaining strict confidentiality. I would not confront the employee or indicate an investigation is ongoing, which could lead to evidence destruction or other complications.

4. Risk Assessment and Containment: Based on the sensitivity of the data accessed and the employee's ability to cause damage, I would evaluate options for limiting potential harm without tipping off the employee. This might include implementing additional monitoring, silently revoking certain elevated privileges, or creating dummy files with trackable watermarks to verify data exfiltration.

5. Coordinated Response: After gathering sufficient evidence, I would work with HR and legal to determine appropriate next steps according to company policy and applicable laws. This could include a formal interview with the employee, account suspension, forensic examination of company-owned devices, and potential involvement of law enforcement if criminal activity is confirmed. Throughout this process, I would ensure proper documentation for potential legal proceedings.

This measured approach helps balance the need to protect company assets while ensuring fair treatment of employees and compliance with privacy laws and company policies.

Scenario 5: Addressing Third-Party Vendor Security Risks

Question: 

Your company is planning to integrate a new cloud-based CRM solution that will house sensitive customer data. During your security assessment, you discover the vendor has experienced a data breach in the past year and several of their security measures don't meet your company's standards. The business team is eager to proceed with this vendor because of significant operational benefits. How would you approach this situation?

Answer:

I would take a risk-based approach that balances business needs with security requirements:

1. Comprehensive Vendor Evaluation: I would do an in-depth vendor security evaluation beyond the initial results, such as extensive questionnaires, documentation, and possibly third-party verification of their security stance. I'd also emphasize how they reacted to their past breach, what changes were made after, and whether or not they've received independent security certifications since then (SOC 2 Type II, ISO 27001, etc.).

2. Gap Analysis with Risk Quantification: I would record explicit gaps between the vendor's security controls and our requirements, then express the risk exposure each gap holds for our organization and data. This would encompass analysis of regulatory compliance implications (such as GDPR, CCPA, or industry-specific regulations) and possible financial impact of different risk scenarios.

3. Compensating Controls Strategy: Instead of merely rejecting the vendor, I would create a multi-layered security strategy that could potentially make up for vendor weaknesses. This could involve adding extra encryption for data prior to it going to the vendor, better access controls, data loss prevention controls, API security gateways, and additional monitoring of the vendor link.

4. Contractual Provisions: I would cooperate with attorneys to make contractual provisions more robust, such as particular security requirements with quantifiable standards, recurring audit rights, obligatory breach notice terms, liability clauses, and even mandating the vendor having cyber insurance coverage for our potential losses.

5. Risk-Acceptance Framework: Where risks are not able to be mitigated technologically or contractually, I would develop a formal risk acceptance document specifying the residual risks involved, the possible business effect, and recommendations. This would be submitted to executive management in addition to the business case to provide an informed risk-acceptance choice at the right management level with proper documentation.

This methodology recognizes that security should facilitate business goals while ensuring protection and provides leadership with the intelligence to make informed risk decisions instead of just hindering forward motion.

Cyber Security Analyst Technical Interview Questions

1. Can you explain the difference between symmetric and asymmetric encryption, and provide an example of when you would use each?

Symmetric encryption utilizes the same secret key for both locking and unlocking the data. It's similar to having a single house key that everyone that needs it must share. This is quick but dangerous if the key is stolen.

Asymmetric encryption involves two different keys - a public key (to lock) and a private key (to unlock). Imagine having a mailbox where anyone can deposit mail (public key), but you alone have the key to open and retrieve the mail (private key).

I'd employ symmetric encryption when one needs speed and the key may be shared securely, such as encrypting files on your computer. I'd employ asymmetric encryption in secure internet communications, such as when you're making a purchase on the internet or logging into your bank.

2. Walk me through how you would investigate a potential data breach from initial detection to resolution.

When we're trying to investigate a breach, I would:

• First, verify that it's actually happening by checking for strange patterns in logs or alerts

• Lock down the issue by isolating hit systems so they can't cause more harm

• Carefully gather evidence before something is altered or erased

• Discover how attackers entered and what they accessed or stole

• Erase the attackers entirely and close up security vulnerabilities they exploited

• Assist systems in returning to normal operation in a safe manner

• Document everything for legal reasons and to avoid future violations

3. What are some common indicators of compromise (IOCs) you look for when analyzing network traffic logs?

When browsing through network logs, I look for:

• Unexpected outbound connections to foreign or unusual IP addresses

• Uncharacteristic login hours or places (such as an employee "logging on" at 3 AM from a different country)

• Excessive data going out of the network (possible data theft)

• Several failed login attempts (an intruder attempting to guess passwords)

• Communication to known bad addresses (such as malware control servers)

4. How would you harden a Windows server that will be exposed to the internet?

To secure a Windows server that is internet-connected, I would:

• Install only the required services and uninstall everything else

• Install all security patches and updates as soon as they're made available

• Implement strong passwords and multi-factor authentication

• Set up the firewall to permit only essential connections and block all else

• Enable extensive logging to trap suspicious behavior

• Install and set up antivirus/anti-malware protection

• Set up limited user accounts rather than using admin accounts for routine tasks

• Disable unnecessary features such as USB access if not required

5. Explain the concept of privilege escalation and how you would detect and prevent it in a corporate environment.

Privilege escalation is when a person acquires greater computer rights of access than they are entitled to - such as an ordinary user somehow becoming an admin.

To identify it, I would:

• Track for unexpected admin account creation

• Watch out for unusual access to secure files or systems

• Check for peculiar software installations or system modifications

• Configure alarms for changes in security settings

To avoid it, I would:

• Grant users the minimum rights they require to perform their work

• Keep all systems and software current with security patches

• Require approval to install any programs

• Use strong passwords and unique accounts for unique levels of access

• Regularly audit who has what accesses to catch out-of-place access