Top 50 Ethical Hacking Interview Questions and Answers

Ethical hacking is the practice of testing a system for vulnerabilities that could be exploited by malicious individuals. Ethical hackers use various methods, such as penetration testing and network analysis, to identify weaknesses in target systems. These attacks are conducted in order to determine the extent of damage that can be caused if these flaws were exploited by an unauthorized user. 

In this article,  we have covered the top 50 Ethical Hacking interview questions with their answers.

1. What is a network sniffer?

A network sniffer monitors the flow of data over computer network links. By allowing you to capture and view packet-level data on your network, the sniffer tool can help you identify network problems. Sniffers can be used both to steal information from a network and for legitimate network management.

Please refer to the article What is Packet Sniffing for more information.

2. How can you avoid ARP poisoning?

There are several approaches to preventing ARP Poisoning attacks:

• Using  Static ARP Tables
• Using Switch Security
• Using Physical Security
• By Network Isolation
• Using Encryption

Please refer to How to Avoid ARP Poisoning? to know more.

3. What are the phases of hacking a system?

• Reconnaissance: This is the first phase where the Hacker tries to collect information about the victim.
• Scanning:  This phase involves the use of apps like dialers, port scanners, and network mappers.
• Gaining Access: In this phase, data collected in Phase 1 and Phase 2 is used to design a blueprint for the hacker.
• Maintaining Access: Once the hacker first gains access to a system, he or she attempts to keep access for future attacks and exploitation.
• Clearing Tracks (so no one can reach them): The attacker would change the MAC address so they could use multiple attacker machines to disguise their identity. They would close. 

Please refer to Phases of Hacking for more details.

4. What are the different ethical hacking tools?

There are various types of ethical hacking tools available. Some of them are as follows:

• Nmap
• Nessus
• Nikto
• Kismet
• NetStumbler
• Acunetix
• Netsparker
• Intruder

Please refer to Top 5 Industry Tools for Ethical Hacking for more details.

5. Why is Python utilized for hacking?

Python provides simplicity and the reader will be able to complete their task faster and easier. Python libraries are also used for coding, recording, network scanning, and network attack.

Please refer to Ethical Hacking with Python article for more information.

6. What are Pharming and Defacement?

• Pharming: In this method, the hacker compromises the DNS servers or on the user’s PC with the goal that traffic is headed toward a malicious site.
• Defacement: In this strategy, the attacker replaces the firm’s site with an alternate page. It contains the hacker’s name, and images and may even incorporate messages also.

For more details please refer Pharming Attack Prevention and Examples article.

7. Different types of buffer overflows and methods of detection?

• Stack-based buffer overflows: This method is used when an attacker sends malicious code which contains stack data, a malicious abstraction of this is fake data Heaps are used to organizing large groups of memory within applications.
• Heap-based buffer overflows: Heap-based attacks are more difficult to perform than stack-based methods. It includes attacks that destroy system memory space beyond the memory it uses for current performance.
• Format string attack: The format character, sometimes known as the format out, shows that the input transformation operations are not always successfully completed. This allows the attacker to use code, read data from the stack, or cause partitions in the application. This may trigger new actions that threaten the security and stability of the system.

8. What is Burp Suite? 

Burp Suite is a collection of tools used to test whether access to a web application has been compromised. It was developed by a company called Portswigger, also named after its founder. Burp Suite aims to have it all in one set of tools and BApps.

For more details refer to What is Burp Suite? article.

9. Define the term Script kiddies?

We can consider them dangerous hackers. These hackers script a scam and use tools that work on the spam that they have received. They are like unskilled Professionals who try to attack computer systems and networks and corrupt websites. Their main intention is to impress their friends and community. Generally, Script Kiddies are people without knowledge of hacking.

For more information refer to the article: Types of Hackers

10. Explain the function of Directory Transversal Attack?

Directory traversal attacks work by abusing one or more  FILE_ATTRIBUTE_NORMAL or FILE_ATTRIBUTE_HIDDEN attributes. When a user accesses a file or folder, the file system will check to see if the attribute is set to one of the allowed values. If it is not, the system will attempt to set the attribute to the correct value. If the attack succeeds, the adversary will be able to access files and folders that they would not be able to access if the attribute was set to the allowed value.

For more details refer to the article: Directory Traversal Attack.

11.  Explain Web Server Hardening Methods?

While hardening internet servers, ensuring server safety is an important element of a vulnerability assessment program. Hackers should utilize Internet infrastructure flaws and systems assigned to serve those flaws and points of connectivity to gain access. Then allow them to have more actions on any system.

Web server hardening involves:

• Managing SSL/TSL certificates and their settings to make certain invulnerable conversations between the purchaser and server.
• Restricting get right of entry to permissions to the internet server set up directory.
• Modifying the configuration file to cast off server misconfigurations.

12. What is NTFS File Streaming?

NTFS File Streaming is a mechanism that allows applications to require access to files stored on an NTFS volume while the volume is offline. This feature can be used by applications that need to temporarily read or write data from an NTFS volume without having to wait for the file system service layer (FS Layer) on which the VolumeMountPoint resides, as well as applications accessing legacy systems where FS layers were not always implemented. 

For more details please refer to the article NTFS Full Form.

13. what is HMAC (Hashed Message Authentication Code)?

HMAC is an encryption algorithm for enforcing message authenticity. If HMAC is used with SSL or TLS to provide messages. It is also a cryptographic hash function that calculates a message digest on data. The export (or generation) of outputs is the unique representation of the data functions. HMAC is worth mentioning because it can provide security when transmitting data over a network.

14.  How to Sniffer Works in ethical hacking?

In ethical hacking, a sniffer is an application that collects data from the target system. Sniffers are used in order to gain access to systems and networks without being detected by the administrator or users of those systems. A sniffer examines packets that are being sent over a network.

For more details please refer to the article Introduction to Sniffers.

15. Describe how you would prevent session hijacking?

Here are some tips and advice to protect against session hijacking:

• We can use Content security policy ( CSP ) and Cross-site Scripting protection headers.
• We can use directive HTTP only for session cookies and by avoiding cookie reuse.
• We can use server-side cookie invalidation on logout.
• By using HTTPS and HSTS on any website.
• By using anti-CSRF( Cross-site request forgery)  tokens on sensitive actions

Please refer to Session Hijacking for more details.

16. Explain the principle of wireless sniffers to locate SSIDs?

Wireless sniffers are commonly used to locate the SSIDs for a wireless network. The analyst can use the wireless sniffers to capture the packets being transmitted, and received on the wireless network and then use the packets to identify the SSIDs for the network.  The analyst can also use the wireless sniffers to determine the mac addresses of the machines on the network.

17. What to do after a security breach occurs?

In case of security or data breach occurs to your company, you must follow these steps:

• Firstly notify your clients and customers.
• Disclose the information that is necessary and mandatory to your clients or customers.
• Always instruct your clients and customers on the next step.
• Verify the source of breach notification.
• Change all admin passwords and secure all LAN networks.

For more details please refer to Data Breach article.

18. What is the main purpose of penetration testing?

The penetration testing process is a key function of information security management. Penetration testing is used to identify vulnerabilities and assess the risk posed by unauthorized access, use, disclosure, or disruption of computer systems or data. Mitigating software vulnerabilities refer to actions that will prevent intruders from stealing sensitive information, hacking into a computer system, or gaining access to protected networks. A system vulnerability is an unspecified fault in a computer system that gives unauthorized persons access to confidential information or the ability to control or damage the secured realm.  Here, information means knowledge that is used to its advantage.

Please refer to PEN Testing in Software Testing for more details.

19. What is Evil Twin or AP Masquerading?

In general, the term “evil twin” or “AP Masquerading” refers to a duplicate or look-alike person or computer program that a hacker might use to attack another person or organization. Organizations sometimes use other companies’ “AP” systems and infrastructure to achieve their goals. The term “access point” is also used to describe. APs or evil twins might be used to conduct reconnaissance, establish a foothold in a network, steal secrets, or launch cyber attacks.

20. What is coWPAtty in ethical hacking?

For some people in the ethical hacking field, the term “coWPAtty” is used to describe an easy target; however, there is zero real. A coWPAtty refers to systems or networks that are not protected with standard security measures and have low levels of protection. Systems on which coWPAtties occur can be found anywhere – at home, at work, or even in public places such as airports and restaurants. 

There are many reasons for a systems attack: 

• Unprotected servers may be exposed online because they lack basic firewalls.
• Outdated types of software or unsecured passwords go undetected by some businesses. 

21. What are GREY areas in the company?

Grey areas may be areas that companies want to avoid publicly addressing, but they are still areas of concern. Initiate a process to identify and assess the various grey areas of your business to determine if there are any areas of risk that need immediate attention. Once risks are identified, a proper plan of action should be taken.

22. What is cross-site scripting and explain the types of cross-site scripting?

Cross-site scripting (XSS) is also called script injection. Scripts are written by the malicious party and injected into websites to commit fraud. The different types of cross-site scripting attacks include stored and reflected XSS vulnerabilities. Stored XSS attacks include injecting malicious codes and scripts into data files that are used by the websites, while reflected XSS exploits vulnerable pages on other websites and injects the attacker’s malicious script back into those pages. 

There are three types of cross-site scripting: 

• Reflected XSS: Reflected XSS arises when user input is evaluatively tainted and then returned in an HTML form to a web application.
• Stored XSS: When website applications save user data such as passwords and information, a stored XSS is possible when that information is then somehow requested. 
• Unevaluated XSS:  When an attacker discovers a vulnerability in a website by unevaluated user input, the attacker can embed arbitrary code in the webpage.

Please refer to What is Cross-Site Scripting (XSS)? for more details.

23. What is CRSF ( Cross-site request forgery )?

CRSF is like a cyberattack where an attacker tricks someone into clicking a malicious link, the user’s browser instead sends the information to the attacker: ex. Yahoo, Google, eBay, etc. CRSF attacks can be carried out by exploiting vulnerabilities in web browsers, PDF readers, and other software that allows users to submit form data directly from their browsers. In terms of CSRF vulnerabilities, sometimes the vulnerability affects more than one area. A two-factor code can result. For example, in an attack, the attacker may inject code into a web page that is viewed by users.

Please refer to What is Cross-Site Request Forgery (CSRF) for more details.

24. What are NetBIOS DoS attacks?

A NetBIOS attack is a method of engaging an attack from infected computers by sending packets of information that interfere with the victim. This can cause serious damage to businesses because they rely on their networks for communications, file sharing, and other essential functions. To attack a NetBIOS system by sending a large number of NetBIOS query requests, an attacker can use the targets of a NetBIOS DoS Attack are usually computers on a network that are used by the company or organization that is being attacked. The attacker’s goal is to prevent these computers from working, and he or she does this by sending bogus name service requests to the computers.

25. What are the components of physical security in ethical hacking?

Physical security is the process of protecting an entity from unauthorized access, use, or destruction. Physical security encompasses a range of measures and technologies used to protect assets from physical harm as well as theft and sabotage. A security building creates controlled pathways so that people entering the building can be identified, and things protected inside the building can be kept secure. The goal of a security building is to create barriers or controlled pathways into this space and ensure that things inside the space remain the various components of physical security that can be collectively used to thwart an intruder. Access control can be used to allow only individuals who are assigned authorization to enter the area and make sure their conduct inside does not violate the rules. Data encryption is used to protect data while it is in transit or while it is stored on the protected system.

26. Explain the term google hacking database?

Google Dorking Method or Google Hacking Database is a process by which someone accesses information that they are not authorized to obtain. The term “dork” was originally used within the online world to describe somebody who searched for unimportant and irrelevant information on the internet in order to liven up their search experience, often with humorous results. Dorks have become associated with those who use illegitimate methods such as hacking into databases and searching through private emails without permission.

Please refer to Fast Google Dorks ScanFast Google Dorks Scan for more details.

27. What are the steps involved in performing enumeration?

Enumeration is the process of identifying all devices connected to a network, system, Organization, or individual. In ethical hacking, enumeration is used to probe the security of an organization’s systems by identifying any potential vulnerabilities that may be exploited during attacks. The vulnerability assessment process begins with making a determination about what constitutes the system under assessment. It is the goal of Security Operations Center/Security Operations Programs (SOC/SOP) programs to analyze and effectively deal with security vulnerabilities. Eventually, those action plans may even result in companies.

Please refer to the article Cyber Security – Types of Enumeration for more details.

28. What are the countermeasure techniques in preventing trojan horses?

In order to protect yourself from trojan horses you need to follow the below steps:

• Never download/install any kind of software from a source you don’t trust completely.
• Never open any attachments or files without knowing whether the source is genuine or not.
• Always update software and applications.
• Always use licensed versions of any kind of software and applications.
• Use anti-virus tools for a safe desktop environment.

Please refer to the article Trojan Horse in Information Security for more details.

29. Define the Target of Evaluation (TOE)?

The TOE is typically used to help ethical hackers develop a better understanding of the goals of the engagement and to measure the effectiveness of the investigative process. The purpose of the TOE is to provide ethical hackers with a framework in which they can more easily identify whether their objectives are being met. The TOE helps to define the parameters of the hacking engagement, as well as to measure the progress and success of the investigative process. The TOE can also be used to identify potential risks and vulnerabilities.

30. What is the difference between banner grabbing and OS fingerprinting?

31. Name some steganography technologies used in system hacking?

Steganography technology is used in system hacking for different reasons such as hiding malicious files, making viruses, and causing mischief by modifying the content of seemingly infected documents. There are different types of steganography technologies given below:

• Text Steganography
• Audio Steganography 
• Video Steganography 
• Image Steganography
• Network Steganography

32. How to cover your tracks and erase evidence on any kind of system during the hacking process?

There are certain steps that a hacker undergoes in order to cover their tracks and erase any evidence of their hacking activity. One of the most important steps is erasing any traces of malware or data taken during the attack. Hacking tools such as sniffers, password crackers, and keyloggers should also be deleted if they were used during the attack. The hacker should also disable all security measures on target systems so that no one can track them down later. Among the most common are proxy servers and VPNs. By using these tools, a hacker can disguise their true IP address and encrypt their traffic, making it harder for authorities to track them down.

33. What do you mean by dumpster diving?

Dumpster diving describes the practice used for retrieving information, computer data, or other confidential information, by searching through waste receptacles that are not intended for public inspection. Dumpster diving can be done legally or illegally. However, it is most commonly conducted illegally. Dumpsters are often placed near businesses in order to collect discarded material from employees and customers who have left their personal belongings behind as they leave work. This material may include files containing private information such as credit card numbers and login credentials for online accounts.

34. What is OWASP? Give some examples of OWASP’s top 10 web vulnerabilities?

OWASP is an Open Web Application Security Project. OWASP is an organization that specializes in improving the security of web applications. The organization maintains a comprehensive database of vulnerabilities and attacks and frequently releases advisories to warn developers about specific security threats. 

The Top 10 web vulnerabilities are some of the most commonly exploited vulnerabilities, and many other vulnerabilities exist that are less commonly exploited. These top 10 vulnerabilities are given below:

• Broken Access Control
• Cryptographic Failure
• Injection
• Insecure Design
• Security Misconfiguration
• Vulnerable and Outdated Components
• Identification and Authentication Failure
• Software and Data integrity Failure
• Security Logging and Monitoring Failure 
• Server-Side Request Forgery

Please refer to the article OWASP Top 10 Vulnerabilities And Preventions for more details 

35. List some intrusion detection systems and evasion techniques in ethical hacking

In cybersecurity, an intrusion detection system (IDS) is a computer security technology that detects unauthorized activity in an organization’s systems. The evasion techniques are methods used to bypass or disable information security measures. Here are some intrusion detection systems and evasion techniques: 

• Packet Fragmentation
•  Source Routing
•  Source Port Manipulation 
• IP Address Decoy 
• Spoofing the IP Address 
• Customizing Packets 
• Randomizing the order of Host
•  Sending the Bad Checksums

36. What is meant by Blowfish algorithms in cryptography?

Blowfish algorithms are a specific family of cryptography algorithms. These algorithms are used in low-level cryptographic applications, such as protecting the confidentiality and integrity of data while it is being transmitted over an insecure channel. Blowfish algorithm employs a 64-bit block cipher that operates on 8 rounds of keys generated by some polyalphabetic function with high probability. A Blowfish algorithm is based on the concept of substitution cipher. In a substitution cipher, each letter of the alphabet is replaced by a different symbol, so that each letter appears only once.

37. Explain how the “Netcat” Trojan works?

Netcat trojans are computer viruses that give an attacker complete control over an infected computer. The malware creates a backdoor on the target system, allowing attackers to access all data and files stored on the device. This includes the ports used by popular web applications such as Gmail, PayPal, and Facebook. By manipulating network traffic, the Trojan can capture sensitive data, install malware, and perform phishing attacks. A malicious attacker can also use the Netcat Trojan to attack other systems on the same network or launch a Distributed Denial of Service (DDoS) attack.

38. What are bypassing the limitations of switches?

There are many switches that can be used in networking, but some of them have certain limitations. Bypassing the limitations of switches helps to improve network performance and increase bandwidth utilization. Switches with bypass features are available as standalone units or they can also be integrated into a Network Management System (NMS). Bypassing the switch’s limitations can have a number of benefits. By bypassing the switch’s normal limitations, the switch can be used to achieve higher system performance. For example, a bypass switch that is capable of switching AC currents at a maximum of 1000 amps can be used to switch DC currents at a higher voltage. This can greatly improve the system’s reliability and performance.

39. What are Smurf and SYN Flood Attacks?

40. Explain Escalating Privileges in system hacking?

In computer hacking, the term “escalating privileges” is often used to describe the process of gaining access to more sensitive systems or data. This process typically begins with an individual gaining access to a lower level of security in order to perform more complex or sensitive tasks. Once the individual has achieved a level of trust and confidence within the system, they are more likely to attempt to break into more sensitive areas of the system.

41. Explain Rootkit Countermeasures in ethical hacking?

A rootkit is a type of malicious software that hides from detection by OS security features. Rootkits have been used for years to secretly install malware on computers without the user’s knowledge or consent. Today, they are also being used as tools for cybercrime and espionage. Rootkit countermeasures (RKC) are a key part of ethical hacking because they allow systems administrators to detect and remove rootkits before they can do damage. RKC techniques can be divided into two main categories: signature-based methods and heuristic methods. When it comes to conducting ethical hacking tasks, the installation of a rootkit countermeasure is one of the most important measures that are taken. Rooting and removing a rootkit are the two most important countermeasures that need to be taken in order to protect the computer system from being compromised.

42. Discuss Linux Hardening Methods?

Linux Hardening Methods are a must for every Linux System Administrator. These methods help in protecting the system from various threats and vulnerabilities. Linux Hardening Methods can be broadly classified into two categories:

• Mandatory: Mandatory Linux hardening methods can help to protect your system from various attacks and vulnerabilities. By installing security updates and security enhancements, as well as disabling unnecessary services, and removing unneeded files, you can tighten the security of your system.
• Recommended: The recommended hardening of the Linux system is to install security-enhancing software. This software will protect the system from known attacks and vulnerabilities. Some of the most common security-enhancing software applications are antivirus, firewalls, and intrusion prevention systems. It is important to carefully select the appropriate software for your system, in order to achieve the best results.

Please refer to the article Top 10 Linux Server Security Tips for more details.

43. Discuss vulnerability in the Windows operating system?

A common vulnerability in Windows is the use of vulnerabilities in the operating system. These vulnerabilities are used to exploit the security of the computer. Once the attacker has exploited a vulnerability in the operating system, they can gain access to the computer. This type of attack is used to steal data or to install malware on the computer.

44. List out some Penetration Testing deliverables?

Here are some most common Penetration Testing Deliverables:

• Testing Strategy
• Testing Plans 
• Testing Data
• Testing Scenario
• Testing Cases
• Requirements Traceability Matrix
• Testing matrix
• Testing Incident report
• Testing Status report
• Testing summary report
• Release Notes
• Testing vulnerability discloser report

45. Describe types of vulnerability assignments?

Here are the types of vulnerability assignments :

• Initial Assessment: Initial level vulnerability assignments are a routine activity that is recommended to identify and protect critical systems from unauthorized access.
• System Baseline: A system baseline definition is a document that lists all the system’s known vulnerabilities, along with recommended solutions. By documenting these vulnerabilities and their solutions, your organization can create a baseline from which to make vulnerability assignments.
• Vulnerability Scan: A vulnerability scan is a routine security procedure that is performed on a computer system or network in order to identify potential security vulnerabilities.
• Vulnerability Assessment Report:  A vulnerability assessment report (VAP) is a document prepared in order to identify and assess risks associated with a system or network. VAPs can be created for a wide range of systems, including but not limited to the IT infrastructure, applications, and the data that resides on those systems.

46. List out some methods for password hacking?

• USB Drives and Social Engineering: USB Drives are becoming more and more popular as storage devices for computers. USB drives come in a variety of shapes and sizes, making them convenient to carry around with you wherever you go. Social engineering is the practice of manipulating someone into revealing personal information or performing an act against their will by exploiting vulnerabilities in that person’s behavior or attitudes.
• DiskFiltration Attacks: DiskFiltration attacks can be carried out using various means such as malware infection, spyware installation, and spear-phishing emails sent to employees. They are used in order to gain access to sensitive information or compromise the security of systems.
• Analyzing Fans With Fansmitter:  Fansmitter is a social media analysis tool that helps organizations understand their fans. It allows administrators to identify, track, and analyze the behavior of their followers on various social networks. Fansmitter also provides insights into what content resonates with them and where they are spending their time online.
• BitWhisper– BitWhisper is a popular ethical hacking tool that helps hackers to scan for vulnerabilities on the targeted computer. It uses social engineering and penetration testing techniques in order to identify weak points in an organization’s security.BitWhisper can also be used by businesses as part of their risk assessment process.

For more details please refer to the article: 5 Common Hacking Techniques Used by Hackers.

47. Give examples of some automated penetration testing tools?

Here are some automated penetration testing tools:

• Nessus
• Metasploit
• Astra vulnerability scanner
• Openvas
• BurpSuite
• Nikto
• Nmap
• SQLmap

Please refer to the article Kali Linux – Web Penetration Testing Tools for more details.

48. What are rogue access points?

Rogue access points are devices that have been deliberately added to a network without the knowledge or consent of the authorized person. These unauthorized devices can be used by attackers to gain an advantage over other networks and systems connected to them. Rogue access points can also provide an attacker with a way into networks protected by firewalls and intrusion detection/prevention systems (IDS/IPS). 

49. Describe XML entity injection?

XML entity injection is a technique that attackers use to inject arbitrary XML content into an HTTP request sent by a web browser. An XML entity injection payload is a type of cyber attack that uses malicious XML documents to exploit CVE-2015-1539, an “arbitrary file upload vulnerability in the Apache HTTPD server. By understanding how XML entity injection payloads work, organizations can help protect their systems from these attacks.

50. List out some tools for network scanning and analysis?

Here are some common tools for network scanning and analysis:

• Nmap:  Nmap is one of the most popular tools for exploring the network and available security control. It has long been used for penetration testing, forensic analysis, security research, and privileged user identification (PUD).
• Burpsuite: The burp suite tool is a command-line interface (CLI) to manage and monitor the security of systems. It automates many common tasks that are needed for penetration testing, such as gathering system information, performing reconnaissance scans, establishing vulnerabilities, installing exploits, and bypassing protection measures. The burp suite tool has been designed with the ethical hacker in mind and can help them achieve their goals while abiding by ethical hacking principles.
• Wireshark: Wireshark is a network protocol analyzer and is mainly used for network troubleshooting but it can be used for ethical hacking as well.
• Cain and Able: Cain and Able tools are ethical hacking tools that can be used by penetration testers to test the security of a computer system. Caine is a powerful automated vulnerability scanner that uses scanning techniques to find vulnerabilities in systems. The software also includes an exploit pack for finding zero-day exploits on vulnerable systems. Able is an auditing tool that helps administrators track changes made to files, Registry keys, Services, and startup items on computers.
• NCAP: The NCAP tool is used for ethical hacking. The NCAP tool helps in identifying the different vulnerabilities on a computer system and can be used to exploit these vulnerabilities for data theft, online fraud or even attacking other systems. Ethical hackers use this software primarily to find out the weaknesses of networks, servers, and individual computers so that they can be fixed by security experts before attackers gain access to them.

Please refer to the article Scanning and its Tools for more details.