Cyber Security Interview Questions

Cybersecurity is the act of protecting computer systems, networks, programs, and data from digital attacks, unauthorized access, damage, or theft. Cybersecurity is a critical aspect of modern technology, with its importance growing as digital systems become increasingly integrated into our daily lives. With threats ranging from data breaches to malicious software attacks, the need for skilled cybersecurity professionals is higher than ever. They typically aim to access, alter or destroy sensitive information, extort money from users, or disrupt normal business processes.

Here, We covered the Top 60 cyber security interview questions with answers suitable for beginners and experienced professionals . It covers everything from basic cybersecurity to advanced cybersecurity concepts such as Threat Intelligence, Incident Response, Malware analysis penetration testing, red teaming and more.

Cyber Security Interview Questions

Whether you are a fresher or an experienced cybersecurity architect, this article gives you all the confidence you need to ace your next cybersecurity interview.

Table of Content

Cyber Security Interview Questions for Freshers

1. What are the common Cyberattacks?

Some basic Cyber attacks are as follows:

For more details please refer to the article: Types of Cyber Attacks

2. What are the elements of cyber security?

There are various elements of cyber security as given below:

For more details please refer to the article: Elements of Cybersecurity

3. Define DNS?

The Domain Name System (DNS) translates domain names into IP addresses that browsers use to load web pages. Every device connected to the Internet has its own IP address , which other devices use to identify it in simple language, we can say that DNS Defines the Service of the network.

To know more please refer to the article: Domain Name System (DNS) in Application Layer

4. What is a Firewall?

A firewall is a hardware or software-based network security device that monitors all incoming and outgoing traffic and accepts, denies, or drops that particular traffic based on a defined set of security rules.

Please refer to the article: Introduction of Firewall to know more about this topic.

5. What is a VPN?

VPN stands for Virtual Private Network. A virtual private network (VPN) is a technology that creates a secure, encrypted connection over an insecure network like the Internet. A virtual private network is a method of extending a private network using a public network such as the Internet. The name only indicates that it is a virtual “private network”. A user may be part of a local area network at a remote location. Create a secure connection using a tunnelling protocol.

Please refer to the article: Virtual Private Network (VPN) to learn more about this topic.

6. What are the different sources of malware?

The different sources of malware are given below:

Please refer to the article: Different Sources of Malware to learn more about this topic.

7. How does email work?

When a sender uses an e-mail program to send an e-mail, it is redirected to a simple e-mail transfer protocol. In this protocol, the recipient’s email address belongs to a different domain name or the same domain name as the sender (Gmail, Outlook, etc.). After that, the e-mail will be stored on the server, and later he will send it using the POP or IMAP protocol. Then, if the recipient has a different domain name address, the SMTP protocol communicates with the DNS (Domain Name Server) for the different addresses that the recipient uses. Then the sender’s SMTP communicates with the receiver’s SMTP, and the receiver’s SMTP performs the communication. This way the email is delivered to the recipient’s SMTP. If certain network traffic issues prevent both the sender’s SMTP and the recipient’s SMTP from communicating with each other, outgoing emails will be queued at the recipient’s SMTP and finally to be received by the recipient. Also, if a message stays in the queue for too long due to terrible circumstances, the message will be returned to the sender as undelivered.

Please refer to the article: Working of Email to learn more about this topic.

8. What is the difference between active and passive cyber attacks?

Please refer to the article: Difference between Active Attack and Passive Attack to know more about it.

9. What is a social engineering attack?

Social engineering is the act of manipulating individuals to take actions that may or may not be in the best interests of the “target”. This may include obtaining information, obtaining access, or obtaining a goal to perform a particular action. It has the ability to manipulate and deceive people. A phone call accompanied by a survey or a quick internet search can bring up dates of birthdays and anniversaries and arm you with that information. This information is enough to create a password attack list.

Please refer to the article: Social Engineering to know more.

10. Who are black hat hackers and white hat hackers?

Please refer to the article: Types of Hackers to know more.

11. Define encryption and decryption?

Encryption is the process of transforming an ordinary message (plaintext) into a meaningless message (ciphertext). Decryption is the process of transforming a meaningless message (ciphertext) into its original form (plaintext). The main difference between covert writing and covert writing is that it converts the message into a cryptic format that cannot be deciphered unless the message is decrypted. Covert writing, on the other hand, is reconstructing the original message from the encrypted information.

Please refer to the article: Difference between Encryption and Decryption to know more.

12. What is the difference between plaintext and cleartext?

The plaintext is not encrypted at all and cannot be considered encrypted and Clear text is a text sent or stored that has not been encrypted and was not intended to be encrypted. So you don’t need to decrypt to see the plaintext. In its simplest form.

Please refer to the article: Encryption and Decryption to know more.

13. What is a block cipher?

Block Cipher Converts plaintext to ciphertext using one block of plaintext at a time. Use 64-bit or 64-bit or greater. The complexity of block ciphers is simple. The algorithm modes used in block ciphers are ECB (Electronic Code Book) and CBC (Cipher Block Chaining).

14. What is the CIA triangle?

When it comes to network security, the CIA Triad is one of the most important models developed to guide information security policy within an organization.
CIA stands for:

Please refer to the article: CIA Triad in Cryptography to know more.

15. What is the Three-way handshake?

TCP uses a three-way handshake to establish reliable connections. The connection is full-duplex, with synchronization (SYN) and acknowledgment (ACK) on both sides. The exchange of these four flags is done in three steps: SYN, SYN to ACK, and ACK.

Please refer to the article: TCP 3-Way Handshake to know more about it.

16. How can identity theft be prevented?

Steps to prevent identity theft:

Please refer to the article: Cyber Crime – Identity Theft to know more about it.

17. What are some common Hashing functions?

The hash function is a function that converts a specific numerical key or alphanumeric key into a small practical integer value. The mapped integer value is used as an index for hash tables. Simply put, a hash function maps any valid number or string to a small integer that can be used as an index into a hash table. The types of Hash functions are given below:

  1. Division Method.
  2. Mid Square Method.
  3. Folding Method.
  4. Multiplication Method.

Please refer to the article Hash Functions to know more about this topic.

18. What do you mean by two-factor authentication?

Two-factor authentication refers to using any two independent methods from a variety of authentication methods. Two-factor authentication is used to ensure users have access to secure systems and to enhance security. Two-factor authentication was first implemented for laptops due to the basic security needs of mobile computing. Two-factor authentication makes it more difficult for unauthorized users to use mobile devices to access secure data and systems.

Please refer to the article Two-factor Authentication to learn more about this topic.

19. What does XSS stand for? How can it be prevented?

Cross-site scripting (XSS) is a vulnerability in web applications that allows third parties to execute scripts on behalf of the web application in the user’s browser. Cross-site scripting is one of the most prevalent security vulnerabilities on the Internet today. Exploiting her XSS against users can have a variety of consequences, including Account compromise, account deletion, privilege escalation, malware infection, etc. Effective prevention of XSS vulnerabilities requires a combination of the following countermeasures:

Please refer to the article Cross-Site Scripting (XSS) to learn more about this topic.

20. What do you mean by Shoulder Surfing?

A shoulder surfing attack describes a situation in which an attacker can physically look at a device’s screen or keyboard and enter passwords to obtain personal information. Used to – access malware. Similar things can happen from nosy people, leading to an invasion of privacy.

Please refer to the article Shoulder Surfing to learn more about this topic.

21. What is the difference between hashing and encryption?

Hashing

Encryption

Please refer to the article Hashing and Encryption to learn more about this topic.

22. Differentiate between Information security and information assurance.

Please refer to the article Information Assurance vs. Information Security to learn more about this topic.

23. Write a difference between HTTPS and SSL.

Please refer to the article SSL vs. HTTPS to learn more about this topic.

24. What do you mean by System Hardening?

The attack surface includes all flaws and vulnerabilities that a hacker could use to gain access to your system, such as default passwords, improperly configured firewalls, etc. The idea of ​​system hardening is to make a system more secure by reducing the attack surface present in the design of the system. System hardening is the process of reducing a system’s attack surface, thereby making it more robust and secure. This is an integral part of system security practices.

Please refer to the article System Hardening to learn more about this topic.

25. Differentiate between spear phishing and phishing.

Please refer to the article Phishing and Spear Phishing to learn more about this topic.

26. What do you mean by Perfect Forward Secrecy?

Perfect Forward Secrecy is a style of encryption that creates a temporary exchange of secret keys between the server and client. It is primarily used to call apps, websites, and messaging apps where user privacy is paramount. A new session key is generated each time the user performs an action. This keeps your data uncompromised and safe from attackers. This is separate from special keys. The basic idea behind Perfect Forward Secrecy technology is to generate a new encryption key each time a user initiates a session. So, if only the encryption key is compromised, the conversation is leaked, and if the user’s unique key is compromised, the conversation will continue. Encryption keys generated by Perfect Forward Secrecy keep you safe from attackers. Essentially, it provides double protection from attackers.

Please refer to the article Perfect Forward Secrecy to learn more about this topic.

27. How to prevent MITM?

Please refer to the article How to Prevent Man In the Middle Attack? to learn more about this topic.

28. What is ransomware?

Ransomware is a type of malware that encrypts data to make it inaccessible to computer users. Cybercriminals use it to extort money from the individuals and organizations that hacked the data and hold the data hostage until a ransom is paid.

Please refer to the article: Ransomware to know more about this.

29. What is Public Key Infrastructure?

A Public Key Infrastructure, or PKI, is the governing authority behind the issuance of digital certificates. Protect sensitive data and give users and systems unique identities. Therefore, communication security is ensured. The public key infrastructure uses keys in public-private key pairs to provide security. Public keys are vulnerable to attacks, so maintaining public keys requires a healthy infrastructure.

Please refer to the article: Public Key Infrastructure to know more.

30. What is Spoofing?

Spoofing is a type of attack on computing devices in which an attacker attempts to steal the identity of a legitimate user and pretend to be someone else. This type of attack is performed to compromise system security or steal user information.

Types of Spoofing:

Please refer to the article: What is Spoofing? to know more.

Cyber Security Interview Questions for Intermediate

31. What are the steps involved in hacking a server or network?

The following steps must be ensured in order to hack any server or network:

To know more about this topic please refer to the article: How to Hack a Web Server?

32. What are the various sniffing tools?

Lists of some main Networking Sniffing Tools:

Please refer to the article: Sniffing Tools to learn more about sniffing tools in ethical hacking.

33. What is SQL injection?

SQL injection is a technique used to exploit user data through web page input by injecting SQL commands as statements. Essentially, these instructions can be used by a malicious user to manipulate her web server for your application. SQL injection is a code injection technique that can corrupt your database. Preventing SQL Injection is given below:

To know more about this topic, Please read the article: SQL Injection

34. What is a Distributed Denial of Service attack (DDoS)?

A denial of service (DoS) is a cyber attack against an individual computer or website aimed at denying service to intended users. Its purpose is to interfere with the organization’s network operations by denying her access. Denial of service is usually achieved by flooding the target machine or resource with excessive requests, overloading the system, and preventing some or all legitimate requests from being satisfied.

Please refer to the article: Denial of Service and Prevention to know more.

35. How to avoid ARP poisoning?

Following are the five ways of avoiding ARP Poisoning attacks:

Please refer to the article: How to Avoid ARP Poisoning? to know more.

36. What is a proxy firewall?

The proxy firewall monitors application-level information using a firewall proxy server. A proxy firewall server creates and runs a process on the firewall that mirrors the services as if they were running on the end host.
The application layer has several protocols such as HTTP (a protocol for sending and receiving web pages) and SMTP (a protocol for e-mail messages on the Internet). A proxy server like Web Proxy Server is like a process that mirrors the behavior of the HTTP service. Similarly, the FTP proxy server reflects how his FTP service works.

Please refer to the article: What is a Proxy Firewall? to know more.

37. Explain SSL Encryption.

Secure Socket Layer (SSL) provides security for data transferred between web browsers and servers. SSL encrypts the connection between your web server and your browser, keeping all data sent between them private and immune to attack. Secure Socket Layer Protocols: SSL recording protocol.

Please refer to the article: Secure Socket Layer to know more about it.

38. What do you mean by penetration testing?

Penetration testing is done to find vulnerabilities, malicious content, flaws, and risks. It’s done to make the organization’s security system defend the IT infrastructure. It is an official procedure that can be deemed helpful and not a harmful attempt. It is part of an ethical hacking process that specifically focuses only on penetrating the information system.

Please refer to the article Penetration Testing to learn more about this topic.

39. What are the risks associated with public Wi-Fi?

Please refer to the article Risks Associated with Public Wi-Fi to learn more about this topic.

40. Explain the main difference between Diffie-Hellman and RSA.

Please refer to the article to learn more about this topic.

41. Give some examples of asymmetric encryption algorithms.

Asymmetric key cryptography is based on public and private key cryptography. It uses two different keys to encrypt and decrypt messages. More secure than symmetric key cryptography, but much slower.

Please refer to the article Symmetric and Asymmetric Key Encryption to learn more about this topic.

42. Explain social engineering and its attacks.

Social engineering is a hacking technique based on forging someone’s identity and using socialization skills to obtain details. There are techniques that combine psychological and marketing skills to influence targeted victims and manipulate them into obtaining sensitive information. The types of social engineering attacks are given below:

Please refer to the article Social Engineering: The Attack on Human Brain and Trust to learn more about this topic.

43. State the difference between a virus and worm.

Please refer to the article Difference between Worms and Virus to know more about this topic.

44. Explain the concept of session hijacking.

Session hijacking is a security attack on user sessions over a protected network. The most common method of session hijacking is called IP spoofing, where an attacker uses source-routed IP packets to inject commands into the active communication between two nodes on a network, allowing an authenticated impersonation of one of the users. This type of attack is possible because authentication usually only happens at the beginning of a TCP session. The types of session hijacking are given below:

Please refer to the article Session Hijacking to learn more about this topic.

45. Explain the honeypot and its types.

A honeypot is a networked system that acts as a trap for cyber attackers to detect and investigate hacker tactics and types of attacks. Acting as a potential target on the Internet, it notifies defenders of unauthorized access to information systems. Honeypots are classified based on their deployment and intruder involvement. Based on usage, honeypots are classified as follows:

Please refer to the article What is Honeypot? to know more about this topic.

46. What do you mean by a Null Session?

Null session attacks have existed since Windows 2000 was widely used. However, system administrators do not consider this type of attack when implementing network security measures. This can have unimaginable consequences, as this type of attack allows hackers to obtain all the information they need to access your system remotely. This type of attack is more difficult to execute if the customer is using a newer version of the operating system, but Windows XP and Windows Server 2003 are still the most common.

Please refer to the article Null Session to learn more about this topic.

47. What is IP blocklisting?

IP blacklisting is a method used to block unauthorized or malicious IP addresses from accessing your network. A blacklist is a list of ranges or individual IP addresses to block.

Please refer to the article What is IP blocklisting? to know more about this topic.

48. What are Polymorphic viruses?

“Poly” refers to many and “morphic” refers to the shape. Thus, polymorphic viruses, as the name suggests, are complex computer viruses that change shape as they spread in order to avoid detection by antivirus programs. This is a self-encrypting virus that combines a mutation engine with a self-propagating code. A polymorphic virus consists of:

Please refer to the article Polymorphic Viruses to learn more about this topic.

49. What is a Botnet?

A botnet (short for “robot network”) is a network of malware-infected computers under the control of a single attacker known as a “bot herder”. An individual machine under the control of a bot herder is called a bot.

Please refer to the article Botnet in Computer Networks to learn more about this topic.

50. What is an Eavesdropping Attack?

Eavesdropping occurs when a hacker intercepts, deletes or modifies data sent between two devices. Eavesdropping, also known as sniffing or snooping, relies on unsecured network communications to access data sent between devices.

Please refer to the article Eavesdropping Attack to learn more about this topic.

Cyber Security Interview Questions for Experienced

51. What is the man-in-the-middle attack?

This is a type of cyber attack in which the attacker stays between the two to carry out their mission. The type of function it can perform is to modify the communication between two parties so that both parties feel like they are communicating over a secure network.

Please refer to the article: Man In the Middle Attack to learn more about this topic.

52. What is a traceroute? Why is it used?

Traceroute is a widely used command line tool available on almost all operating systems. A complete route to the destination address is displayed. It also shows the time (or delay) between intermediate routers.

Uses of traceroute:

Please refer to the article: Traceroute in Network Layer to know more about it.

53. What is the difference between HIDS and NIDS?

Please refer to the article: Difference between HIDs and NIDs to know more about it.

54. What is the difference between VA (Vulnerability Assessment) and PT (Penetration Testing)?

55. What is RSA?

The RSA algorithm is an asymmetric encryption algorithm. Asymmetric means that it actually works with two different keys. H. Public and Private Keys. As the name suggests, the public key is shared with everyone and the private key remains secret.

Please refer to the article: RSA Algorithm in Cryptography to know more.

56. What is the Blowfish algorithm?

Blowfish is an encryption technique developed by Bruce Schneier in 1993 as an alternative to the DES encryption technique. It is considerably faster than DES and provides excellent encryption speed even though no effective cryptanalysis techniques have been discovered so far. It was one of the first secure block ciphers to be patent-free and therefore freely available to everyone.

Please refer to the article: Blowfish Algorithm to know more.

57. What is the difference between a vulnerability and an exploit?

Please refer to the article: Difference Between Vulnerability and Exploit to know more about it.

58. What do you understand by Risk, Vulnerability and threat in a network?

59. Explain Phishing and how to prevent it.

Phishing is a type of cyber attack. The name phishing comes from the word ‘phish’, which means fish. Placing bait to catch fish is a common phenomenon. Phishing works similarly. Tricking users or victims into clicking on malicious websites is an unethical practice.

Here’s how to protect your users from phishing attacks.

Please refer to the article Phishing to know more about this topic.

60. What do you mean by Forward Secrecy and how does it work?

Forward secrecy is a feature of some key agreement protocols that guarantees that the session keys will remain secure even if the server’s private key is compromised. Perfect forward secrecy, also known as PFS, is the term used to describe this. The “Diffie-Hellman key exchange” algorithm is employed to achieve this.

Conclusion

In summary, today, implementing effective cybersecurity measures is especially challenging due to the increasing number of devices relative to humans and the constant innovation by attackers. Therefore, cybersecurity professionals must employ various tools and techniques, including encryption, firewalls, antivirus software, anti-phishing measures, and vulnerability assessments, to proactively safeguard against and respond to cyber threats. As a result, the demand for cybersecurity professionals is expected to remain high in the future.

Wondering about the salary of a cyber security analyst? Take a look at our specialized article on Average Cyber Security Salary .

Frequently Asked Cyber Security Interview Questions

1. What is cryptography?

Cryptography is the practice of securing information and communications by transforming them into a form that cannot be easily understood by unauthorized parties. This can be done by using encryption algorithms to scramble the data, making it unreadable without the decryption key. Cryptography is used in a wide variety of applications, including secure communication, data storage, and digital signatures.

2. What is a traceroute? Mention its uses.

3. Define firewall, and why is it used?

4. Why is a firewall used?

5. What is a three-way handshake?

  1. The client sends a SYN packet to the server.
  2. The server sends a SYN-ACK packet to the client.
  3. The client sends an ACK packet to the server.

6. What is a response code?