Updated May 19, 2023

Introduction to Security Testing Interview Questions

Security testing is a process to detect any flaws in the security mechanism that protects the data and maintains the intended functionality. Confidentiality, authentication, authorization, availability, integrity, and non-repudiation are key security elements. If you are seeking a job in security testing, it is important to prepare for the interview. In this article on Security Testing Interview Questions for 2023, we will present the top 20 most important and frequently asked questions. I will divide these interview questions into two parts.

Basic Security Testing Interview Questions
Advanced Security Testing Interview Questions

Note: Along with the answers, we have shared some pro tips to help you sound confident and show the interviewer that you have done your research and know about real events in the field.

Part 1: Security Testing Interview Questions (Basic)

This first part covers the basic interview questions and answers:

Q1. What is security testing?

While asking the question, “What is security testing?” the interviewer is likely assessing your understanding of the fundamental concepts and principles of security testing. You can give a simple definition and purpose while answering.

Sample Answer:
Security testing is a systematic process that executes test cases to identify and expose vulnerabilities in the security mechanisms of information systems. Security testing aims to discover potential weaknesses in applications or systems and safeguard data from potential attackers. Testers assume the role of attackers and simulate various attack scenarios to uncover security flaws.

Pro Tip: To gain bonus points, explain any real company that applies security testing to protect its systems and data, like Google, Amazon, Paypal, Apple, and Microsoft.

Q2. What is SQL injection?

The interviewer is testing if you can explain an SQL injection, how it works, and its potential impact on systems.

Sample Answer:
SQL injection refers to a code injection technique used to attack data-driven systems. It involves inserting malicious SQL statements into input fields with the intention of executing unauthorized commands. Through SQL injection, attackers can manipulate data, impersonate identities, engage in repudiation issues like voiding transactions or altering balances, gain unauthorized access to all system data, corrupt or render data inaccessible, and even assume administrative control over the database server. While commonly associated with website vulnerabilities, SQL injection can target any SQL database.

Pro Tip: Demonstrate your understanding without being too verbose & jargonistic. You can use a simple version to explain this:

“Imagine you have a secret code to open a hidden door in your house. This code is stored in a special room called a database. However, individuals with malicious intentions sometimes try to find a way to trick the database.

SQL injection is that sneaky trick individuals use to enter special commands into website or app input fields connected to the database. By entering unexpected commands, the database becomes confused and malfunctions. This confusion can lead to unauthorized access, enabling them to view private user information or manipulate the database”.

Q3. What is vulnerability?

When the interviewer asks about “vulnerability,” they want to know if you understand how to find weak spots in a company’s systems that hackers can take advantage of. Your answer should demonstrate your awareness of the concept and how it contributes to overall security measures.

Sample Answer:
A vulnerability is simply a weakness or flaw in a system that attackers can exploit. These vulnerabilities can exist in software, hardware, network configurations, etc. Exploiting vulnerabilities can lead to unauthorized access, system compromises, data breaches, or other security incidents. Regular security testing is important to identify and address vulnerabilities, thereby reducing the risk of exploitation.

Q4. What is the intrusion detection system?

The interviewer wants to test whether you know the purpose, system functionality, and any real-world example.

Sample Answer:
Intrusion detection is a system that assists in determining and dealing with possible cyber attacks. After collecting information from various systems and sources, it analyzes the information and finds possible ways to attack the system. Moreover, it also checks for any abnormal activities and alterations in the system data.

Pro Tip: You can support your answer by explaining a real event. Here’s an example:

“I would like to give an example of a real event related to this concept. In 2013, attackers perpetrated a major data breach on Target, one of the largest retail companies in the United States, stealing the credit card and personal information of millions of customers. They had an intrusion detection system called FireEye, however, the system failed to alert Target’s security team due to misconfigurations and inadequate response protocols. But luckily, the intrusion detection system was instrumental in the subsequent investigation and post-incident analysis.”

Q5. What are the 7 attributes of security testing?

When answering this question, you can discuss the important qualities or characteristics that define effective security testing.

Sample Answer:
There are seven attributes of security testing. They are as follows:

Authentication: In authentication, the user’s identity is checked to provide access to the system.
Authorization: In authorization, the user’s authorities are checked to access the resources.
Integrity: Integrity ensures that the data of the system is not altered.
Non-repudiation: It refers to the assurance that someone cannot deny the action they have done.
Confidentiality: It ensures that information is kept private to authenticated users only.
Availability: It ensures that the system, application, and data are available for the user when needed.
Resilience: Resilience is the capability of the entity to deliver the intended outcome continuously despite unfavorable cyber events.

Q6. What is penetration testing?

When the hiring manager asks about penetration testing, they want to see if you understand how it helps find weaknesses in computer systems, networks, or apps to make them more secure.

Sample Answer:
Penetration testing involves detecting loopholes and vulnerabilities in computer systems, networks, or applications. A tester simulates real-world cyber attacks in order to assess the security of an organization’s infrastructure and identify possible loopholes that attackers can exploit.

The process of identifying and exposing vulnerabilities in the security mechanisms of information systems is also known as ethical hacking and white-hat hacking.

Pro Tip: You can enhance your answer by illustrating a real event that exemplifies this concept.

“I would like to highlight a notable case related to penetration testing. This happened in the year 2017 when the US Department of Defense (DoD) organized the “Hack the Air Force” exercise. This was actually a large-scale penetration testing exercise. Ethical hackers from around the world were invited to identify vulnerabilities in the Air Force’s computer systems. Over 3,000 registered hackers conducted authorized testing to uncover potential weaknesses. This initiative successfully enabled the DoD to leverage the hackers’ expertise and proactively address critical security flaws before they could be exploited by real adversaries.”

Q7. What is AdHoc testing?

To answer this question, you can apply your knowledge to identify and fix software problems or bugs in an informal or relaxed testing environment.

Sample Answer:
The AdHoc testing system is an unplanned and informal testing process. It lacks a structured methodology and may require the tester to employ his experience and the system’s knowledge in identifying the probable source of errors. This method can be fruitful in situations where time is limited and formal test case documentation is not possible.

Q8. What is a DDoS attack?

Sample Answer:
A Distributed Denial of Service (DDoS) attack seeks to render a computer network inaccessible to its users. Often utilizing botnets, the attacker floods the targeted computer system by sending a huge number of unnecessary requests from multiple sources, which consequently overloads the system. This leads to the system denying some or all of the requests, as there is no single source to be blocked.

Pro Tip: To make your answer more engaging, you can share a real incident like this one:

“Let me share a real example from 2016. Dyn, a major company that helps connect websites to the internet, experienced a big problem. It was attacked by hackers with a DDoS attack. This caused trouble for popular websites like Twitter, Netflix, Spotify, and GitHub. The attackers used a group of compromised computers called a botnet to flood Dyn’s servers with a huge amount of malicious traffic. This made it difficult for the servers to do their job and caused all these major websites to become temporarily inaccessible to users around the world.”

Q9. What are Botnets?

Sample Answer:
Botnets are often used for DDoS attacks, spamming, and data theft. A botnet can be understood as a network of compromised computers under an attacker’s control for malicious purposes. These are regular personal computers with an internet connection, and their owners are often unaware of the issue.

Q10. What is NIDS?

Sample Answer:

NIDS stands for Network Intrusion Detection System. It analyzes the passing traffic on the entire subset and matches it with the known attacks. The system automatically sends an alert message to the administration in the event of identifying loopholes. In addition, it can work with other systems, e.g., firewalls, to help better protect against known attack sources. It can range from small computers to large computers.

Part 2: Security Testing Interview Questions (Advanced)

Let’s now have a look at the advanced interview questions:

Q1. What is Cookie and its Types?

Answer:
A cookie is a piece of information that a web browser receives from a web server and can be read at any time later. Cookies contain password-based information, auto-fill information, etc.

There are two types of cookies: session cookies and persistent cookies.

Session Cookie: Session cookies are temporary and last in that session only.
Persistent Cookie: Persistent cookies are stored on a hard disk drive and last until their expiry or manual removal.

Pro Tip: You can give names of some real companies that use cookies:

“Some major companies use cookies for various purposes. For example, Facebook uses cookies to keep you logged in and make sure it’s really you. Amazon uses cookies to remember what you added to your cart and give you shopping recommendations. And YouTube uses cookies to suggest videos you might like, remember your preferences, and show you relevant ads.”

Q2. What are the types of Penetration Testing?

Sample Answer:
White-box testing, black-box testing, and grey-box testing are the types of penetration testing.

White-Box Testing: This testing method provides all the information to the testers.
Black-Box Testing: In this method, the tester does not provide any information. They can test the system in a real-time environment.
Grey-Box Testing: This method is a combination of both white-box testing and black-box testing. The tester receives partial information, and they test the remaining on their own.

Q3. What is SSL? List its components.

Sample Answer:
SSL stands for Secure Socket Layer. SSL helps in creating a secure connection between the client and the server. Components of the SSL include recorded protocol, encryption algorithms, handshake protocols, and change cipher specs.

However, SSL has been deprecated and is now replaced by TLS (Transport Layer Security) protocol, which provides greater security. Despite the TLS versions being backward compatible with SSL, the use of SSL is often discouraged due to known security vulnerabilities.

Q4. What is Backend Testing and its Types?

Sample Answer:
Backend testing involves testing the server-side components of a given application or system. Backend testing checks for factors such as performance and functionality of the underlying infrastructure, e.g., databases, APIs, and server applications. The process helps to detect any potential issues or bugs in the system, thereby maintaining its overall efficiency.

There are different types of backend testing, such as:

Structural Testing
Functional Testing
Non-Functional Testing

Each of these testing categories further divides into various subcategories.

Pro Tip: It’s always helpful to back up your answer with a real-life example, like the Facebook outage in 2021.

During that time, Facebook experienced a significant disruption that impacted its front-end services and back-end systems. This event served as a clear reminder of the importance of conducting thorough backend testing to ensure the smooth functioning of the entire system.

Q5. What is URL manipulation in security testing?

Sample Answer:
URL manipulation refers to modifying URL parameters and components for various purposes. Although URL rewriting can help create relevant URLs, one can exploit it maliciously. URL manipulation can aid in identifying loopholes to exploit a system and can even grant the attacker total control of the website. For instance, attackers can employ URL manipulation techniques to access confidential information and protected sections of web pages.

Pro Tip: You can share a real incident related to URL manipulation as follows:

“Let me share an event related to URL manipulation called the “Samy worm.” So, this guy named Samy Kamkar, who was a computer programmer, created a worm on MySpace, which was the popular social networking website at that time. This worm spread by messing around with the user’s profile URL, adding itself as a friend, and then infecting the profiles of that user’s friends. It took advantage of a weakness in MySpace’s system, and spread like wildfire, impacting millions of users!”

Q6. What is Endurance Testing?

Sample Answer:
Endurance testing is simply testing a system with a high load over an extended period of time. This process seeks to ensure that the system can bear enough load without any breakdowns or performance degradation in its working. The testing process can be very long, even up to a year, and is undertaken at the performance run cycle’s last stage. A system that can withstand endurance testing is capable of sustained usage.

Q7. What are the three classes of intruders?

Sample Answer:
There are three classes of intruders:
1. Masqueraders: Masqueraders are outsiders who attain unauthorized access to systems via legitimate user credentials. They masquerade as genuine users and get access to the systems by guessing passwords, utilizing stolen credentials, or even social engineering.
2. Misfeasors: Misfeasors are legitimate users with authorized access but utilize it for unauthorized actions. They are insiders who utilize their privileges and use them for unethical actions, such as stealing or manipulating data.
3. Clandestine User: Clandestine users gain access to the system without getting detected. They bypass security measures and hack into the system for unethical activities such as data theft and service disruption. They can be either outsiders or insiders.

Q8. What is Port Scanning?

Sample Answer:
Ports serve as the entry and exit points of information in a system. Port scanning refers to scanning these points for any possible vulnerabilities and can help for both good and bad purposes. For example, network administrators can evaluate the security structure of a system or network to eliminate loopholes and maximize the system’s security. On the other hand, hackers can employ the method to identify possible entry points for unauthorized access into the system. There are different kinds of ports, such as SYN scan, FTP bounce scan, and TCP connect scan.

Pro Tip: You can share various notable events like the Code Red worm (2001), Mirai botnet (2016), WannaCry ransomware attack (2017), and SolarWinds supply chain attack (2020) that leveraged port scanning to target and compromise vulnerable systems.

Q9. What is SOAP?

When an interviewer asks about SOAP, they may be expecting you to explain what SOAP is, its key features, and its role in web services.

Sample Answer:
Simple Object Access Protocol (SOAP) stands for Simple Object Access Protocol, which is a widely used XML-based protocol. Applications utilize SOAP to communicate and interact with each other over various network protocols, such as HTTP, SMTP, and more.

Q10. What does WSDL stand for?

This question is all about testing your understanding and experience with web services and how well you know the technologies used to work with them.

Sample Answer:
WSDL is the acronym for Web Services Description Language. Developers use an XML-based language to describe web services and the method to access them. WSDL provides a standardized format for defining the structure, operations, and endpoints of a web service.

Quiz Result
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