Penetration Testing Interview Questions and Answers

Penetration Testing (pen-testing or pentesting) is also known as a security assessment. Penetration testing is also commonly referred to as a pen test (or ethical hacking). Penetration testing in simple terms is a simulation of a process a hacker would use to launch an attack on a business network, attached devices, network applications, or a business website.  Pen-testing is implemented by simulating malicious attacks from an organization’s internal and external users. The entire system is then analyzed for potential vulnerabilities.

A plan that communicates test objectives, timetables and resources is developed prior to actual pen-testing.  Or a penetration test is a real-world attack performed by security experts on a company’s IT infrastructure to discover exploitable security flaws. This is different from a vulnerability assessment in that a vulnerability assessment is an inch deep and a mile wide whereas a penetration test is the opposite – a narrow focus, taking exploitation of the furthest extent possible.

Here’s a general overview of how penetration testing works:

1. Planning and Scoping:
   • Define the scope of the penetration test, including the target systems, networks, or applications to be tested.
   • Identify the goals and objectives of the penetration test, such as uncovering specific vulnerabilities or assessing overall security posture.
   • Gather information about the target system, including its architecture, technologies used, and any available documentation.
2. Reconnaissance:
   • Conduct passive information gathering to collect publicly available data about the target, such as IP addresses, domain names, email addresses, etc.
   • Perform active scanning and enumeration techniques to identify potential entry points, open ports, and network services.
3. Vulnerability Assessment:
   • Use specialized tools to scan the target system for known vulnerabilities, such as outdated software versions, misconfigurations, weak passwords, or insecure network protocols.
   • Analyze the results to prioritize vulnerabilities based on their severity and potential impact.
4. Exploitation:
   • Attempt to exploit identified vulnerabilities to gain unauthorized access, escalate privileges, or compromise the target system.
   • Utilize various techniques, including manual exploitation, scripting, or using automated tools, to simulate real-world attack scenarios.
5. Post-Exploitation:
   • Once access is gained, perform further reconnaissance within the target system or network to gather additional information or escalate privileges.
   • Explore the compromised system to understand the extent of potential damage or data that could be accessed.
   • Document the steps taken and vulnerabilities exploited for reporting and analysis purposes.
6. Reporting:
   • Prepare a comprehensive report that includes the findings, vulnerabilities discovered, exploited access points, and recommended remediation steps.
   • Provide clear and actionable recommendations to address the identified vulnerabilities and strengthen the security posture of the target system.

 In Penetration testing, there are different types of penetration testing’s:

• Network Penetration Testing
• Application Penetration Testing
• Embedded System Penetration Testing (Hardware hacking)
• Physical Penetration Testing
• Red Team Engagements.

There are different types of penetration testing methods:

External testing:  It targets a company’s externally visible servers or DNS, E-mail servers, Web servers or firewalls.

Internal Testing: Inside attack behind the firewall by an authorized user with standard access privileges.

Blind Testing: In a blind test, a tester is only given the name of the enterprise that’s being targeted. This gives security personnel a real-time look into how an actual application assault would take place.

Double blind testing:  In this testing security personnel have no prior knowledge of the simulated attack. Double-blind tests can be useful for testing an organization’s security monitoring and incident identification as well as its response procedures.

Target Testing: Targeted testing or the lights-turned-on approach as it is often referred to, involves both the organization’s IT team and the penetration testing team to carry out the test.

A penetration tester knows how to write scripts that automate some of the testing. You can use almost any language to write scripts. Describe the script you wrote and the languages you used. Get ready for the interviewer to ask more details.

Hire an independent third-party IT auditing expert and have them work in partnership with your team. Look for Offensive Security Certified Professional (OSCP) or GIAC Certifited Penetration Tester (GPEN) certification and ask which tools and methodologies they use. 

In advance of every penetration test, an individual meeting is held. In this meeting, the various possibilities of a penetration test in relation to the customer’s systems are discussed. A penetration test only makes sense if it is realized in an individual and customer-oriented way.

Some certifications of Penetration tester

GIAC (Global Information Assurance Certification)

• GCIH (GIAC Certified Incident Handler)
• GSEC (GIAC Security Essentials)
• GWAPT (GIAC Web Application Penetration Tester)
• GPEN (GIAC Penetration Tester) or CEH (Certified Ethical Hacker)
• GXPN (GIAC Exploit Researcher and Advanced Penetration Tester)
• GPYC (GIAC Python Coder)
• GMOB (GIAC Mobile Device Security Analyst)
• GAWN (GIAC Assessing and Auditing Wireless Networks)

 In testing the network layer like firewalls, email servers, web servers, FTP servers, etc. The application layer: all major development languages, all major web servers, all major operating systems, all major browsers.

Wireless systems: internal workstations, printers, fax machines, WAR dialing phone numbers, virtual environments including cloud, internet enabled devices, and more. We have tested law enforcement systems, state and municipal government systems, and private sector systems ranging from online gaming to financial institutions.

• Notice viruses, malware, and spyware on workstations
• After implementing significant any changes in website or network
• Unauthorized traffic on your network noted
• Security audit for HIPAA or PCI-DSS
• After installing any new software or other upgrades
• Prior to contracting and submission of application for breach insurance
• You store any valuable data and have never had one

You can stop authentication after a certain number of attempts and lock the account. You can also block IP addresses that flood the network. You can use IP restrictions on the firewall or serve

Pair testing is a type of ad-hoc testing where pair of testers or tester and developer or tester & user is being formed which are responsible for carrying out the testing of the same software product on the same machine.

Omniquad Border Secure is a service that performs network audits or network penetration testing — it identifies security vulnerabilities and weaknesses on networks. The information can be used to assess security, manage risks, and eliminate security vulnerabilities before third parties can take advantage of potential security holes on your network. Omniquad Border Secure is a service that can tell you how hackers can gain access to your networks, and help you prevent such a security breach.

 In pen test, you can use PGP to encrypt email messages or some other form of a public private key pair system where only the sender and the recipient can read the messages.

Penetration testing should be an integral part of every organization’s risk management strategy because it can help determine whether existing security policies are effective, uncover unknown vulnerabilities and provide organizations an opportunity to remediate the identified vulnerabilities before a data breach occurs.

Data breaches are not only very costly but also impact the reputation of an organization, so a controlled test that detects vulnerabilities an attacker could actually exploit is invaluable.

The HTTP protocol allows for security behind authenticated pages and directories. If the user does not enter the right username and password, the server returns a 403 authentication HTTP error. This protects from unauthorized users.

A hacker can use the man in middle attack with the Diffie Hellman exchange since neither side of the exchange is authenticated. Users can use SSL or encryption between messages to add some kind of security and authentication.

The most common vulnerabilities discovered during a penetration test are related to network configuration. Many of the default systems organizations use to communicate over their network actually allow malicious individuals to capture information as it travels through the network, leaving the organization vulnerable to a data breach. Another very common vulnerability originates from device and service configurations.

For example, leaving the default configuration on a copy machine might not seem harmful, but it provides an attacker the ability to access documents scanned by the printer and other network information that is stored on the device itself.

There are many names for this type of security service. Network vulnerability assessment, network audit, network vulnerability scan, network penetration testing, they may all mean the same thing. BorderSecure is the name of Omniquads Network penetration service.

Traceroute and tracert work to determine the route that goes from the host computer to a remote machine. It’s used to identify if packets are redirected, take too long, or the number of hops used to send traffic to a host.

• Websites
• Commercial off-the-shelf (COTS) or prebuilt equipment and software applications
• Proprietary enterprise applications (EA)
• Potentially compromisable phone and wireless systems
• Physical controls
• Networking

Yes, it is completely safe, skilled Omniquad engineers are probing your network from outside your organization/company. However, if there should be any glitches, it is better that it happens under a controlled sweep of your network since this in itself is exposing network vulnerabilities, some of which could indicate that your business would be defenseless to Denial of Service attacks

It is considered best practice to have both an external and internal penetration test performed on an annual basis. New vulnerabilities are discovered regularly, so it is vital for organizations to stay ahead of evolving threats.

In addition, organizations undergo various IT-related projects throughout the year, so any major configuration changes to the network should be thoroughly tested to guarantee they will not expose the organization to unnecessary risk.

Vulnerability assessment focuses on identifying and quantifying vulnerabilities in a system or network. It typically involves automated scanning tools that identify known vulnerabilities. On the other hand, penetration testing goes a step further by actively exploiting identified vulnerabilities to assess the potential impact of a successful attack.

Penetration testing combines vulnerability assessment with manual testing techniques to simulate real-world attack scenarios.

A zero-day vulnerability refers to a software vulnerability that is unknown to the software vendor or has no official patch available. During penetration testing, if a tester discovers a zero-day vulnerability, they can attempt to exploit it by developing an exploit or proof-of-concept code.

However, it is important to note that responsible and ethical penetration testers do not typically use zero-day vulnerabilities during their engagements unless explicitly authorized by the client or for research purposes.

Prioritizing vulnerabilities involves assessing their severity and potential impact on the system or organization. Common factors to consider include:

• The level of access or privileges an attacker could gain through the vulnerability.
• The ease of exploitation and the likelihood of an attacker exploiting it successfully.
• The potential impact on data confidentiality, integrity, or availability.
• Compliance and regulatory implications.
• The existing mitigations or compensating controls in place.

Validating and demonstrating the impact of a successfully exploited vulnerability is an important step in penetration testing. This can be done by providing evidence, such as capturing screenshots, data exfiltration logs, or access to sensitive information.

Additionally, demonstrating the impact may involve showing how the vulnerability can be leveraged to gain unauthorized access, escalate privileges, or manipulate the target system.

Staying current with the evolving landscape of vulnerabilities and hacking techniques is crucial for penetration testers. Some common practices include:

• Regularly monitoring security news, blogs, and forums.
• Participating in industry conferences, webinars, and training sessions.
• Engaging in hands-on practice and experimentation in lab environments.
• Maintaining relevant certifications and memberships in professional organizations.
• Collaborating with peers and sharing knowledge within the cybersecurity community.

It may not be mandatory to do a penetration test for corporations, but the German law for example includes numerous text passages in its commercial laws which could be validated by conducting a penetration test.

As new security issues and flaws with different products are made public on a daily basis, it is important to carry out regular checks in order to maintain a secure network. We check for holes in your Internet infrastructure, and the ideal way to stay secure on the Internet is to stay ahead of hackers, at all times.

RedTeam Pentesting works for many international customers. The project language for penetration tests is either English or German. Depending on specific customer demands, penetration tests can be performed locally at the client’s premises, or via the Internet or other means of remote access.

It is of course also possible to conduct a penetration test on a client’s test system in RedTeam Pentesting’s laboratory, for example in case of a product pentest.

We have performed single engagements for clients covering more than 4000 IP addresses and thousands of web pages covering many different systems.

Unlike real attackers, Redteam Pentesting pays great attention to a customer’s production systems, so as to not interrupt them. We always go to the greatest extent to leave all systems unharmed in a penetration test. Attacks where the risk of a system failure is especially high are only performed with the client’s explicit consent.

All in all, it is never possible to completely rule out that a production system crashes in a penetration test. To be able to get hold of someone as fast as possible in such a situation, emergency telephone numbers are exchanged prior to the test.