Security Audit

What is Gray Box Penetration Testing?

Updated on: March 16, 2023

What is Gray Box Penetration Testing?

Gray box penetration testing is a type of penetration testing in which the pentesters have partial knowledge of the network and infrastructure of the system they are testing. Then, the pentesters use their own understanding of the system to do a better job of finding and reporting vulnerabilities in it. 

In a sense, a gray box test is a combination of a black box test and a white box test. The black box test is a test that is done from the outside in, with the tester not knowing the system before testing it. A white box test is a test that is done from the inside out, with the tester having full knowledge of the system before testing it. In this blog, we will only discuss gray box penetration testing to provide you enough information on the same.

Why Astra is the best in pentesting?

  • We’re the only company that combines automated & manual pentest to create a one-of-a-kind pentest platform
  • Vetted scans ensure zero false positives
  • Our intelligent vulnerability scanner emulates hacker behavior & evolves with every pentest
  • Astra’s scanner helps you shift left by integrating with your CI/CD
  • Our platform helps you uncover, manage & fix vulnerabilities in one place
  • Trusted by the brands you trust like Agora, Spicejet, Muthoot, Dream11, etc.

Why Gray Box Penetration Testing?

Gray Box Penetration Testing is a method of pen-testing that attempts to combine the best of both the Black Box and White Box methodologies. A successful gray box pentest requires a solid understanding of the target environment before any testing takes place. This unknown approach is why gray box penetration testing service is often used in more controlled environments, such as military and intelligence agencies. However, there is plenty of room for improvement in the application, and the testing can be effectively applied to any environment with the proper planning and experience.

Gray box testing not only allows you to test the security of the network but also the security of the physical environment. It is especially useful when a test involves a breach of a perimeter device, such as a firewall.

Also, gray box tests use a combination of penetration testing techniques, including network scanning, vulnerability scanning, social engineering, and manual source code review. This provides valuable insight regarding the amount of damage a hacker or attacker can create.

How does Gray Box Penetration Testing differ from the black box and white box?

Penetration testing is divided into three categories: black box, white box, and gray box. Let’s understand the differences between these three:

S No.Black Box Penetration TestingGray Box Penetration TestingWhite Box Penetration Testing
1Little or No knowledge of network and infrastructure is required.Somewhat knowledge of the Infrastructure, internal codebase and architecture.Complete access to organization infrastructure, network and codebase.
2Black box testing is also known as closed box testing.Gray box testing is also known as translucent testing.White box testing is known as clear box testing.
3No syntactic knowledge of the programming language is required.Requires partial understanding of the programming language.Requires high understanding of programming language.
4Black box testing techniques are executed by developers, user groups and testers.Performed by third party services or by testers and developers.The internal Development team of the organization can perform white box testing.
5Some standard black box testing techniques are: Boundary value analysis, Equivalence partitioning, Graph-Based testing etc.Some standard gray box testing techniques are Matrix testing, Regression testing, Orthogonal array testing, Pattern testing.Some standard white box testing techniques are Branch testing, Decision coverage, Path testing, Statement coverage.

5 steps to perform Gray box Penetration Testing

Gray box penetration testing is usually performed in 5 different steps mentioned below:

Steps to perform Gray Box Penetration Testing
Image: Five steps to perform gray box penetration testing.

1. Planning and Requirements Analysis:

This phase includes understanding the scope of the application and the tech stack being used. The security team also requests some application-related information, such as dummy credentials, access roles, etc. This phase includes understanding the scope of the application and the tech stack being used. Furthermore, preparing a documentation map is also part of this phase.

2. Discovery Phase:

This phase is also known as Reconnaissance, which includes discovering the IP addresses being used, hidden endpoints, and API endpoints. The Discovery phase is not limited to networks but includes gathering information about the employees and their data, also known as Social Engineering.

3. Initial Exploitation:

Initial exploitation includes planning what kind of attacks will be launched in the later steps. This phase also includes finding misconfigurations in the servers and cloud-based infrastructure. The requested information helps the security team in creating various attack scenarios like privilege escalation etc. Further, behind the login, scanning would also be possible. Further, behind the login, scanning also goes on.

4. Advanced Penetration Testing:

This phase includes launching all planned attacks on the discovered endpoints—execution of Social Engineering attacks based on the collected information of employees. Furthermore, various vulnerabilities found are combined to create real-life attack situations.

5. Document & Report preparation:

The last step is preparing a detailed report of every endpoint tested along with a list of launched attacks.

Top 3 gray box penetration testing techniques

Gray box pentest uses various types of techniques to generate test cases. Let’s understand some of them in detail:

1. Matrix testing

Matrix testing is a technique of software testing that helps to test the software thoroughly. It is the technique of identifying and removing all the unnecessary variables. Programmers use variables to store information while writing applications. Several variables should be as per requirement. Otherwise, it will reduce the efficiency of the program.

2. Regression testing

Regression testing is retesting the software components to find defects introduced by the changes made previously or in first the testing iteration. Regression testing is also known as retesting. It is performed to ensure that weaknesses are not introduced or reintroduced into a software system by modifications after the initial development. Regression Testing is an essential part of software testing because it helps to ensure that newly introduced software features continue to work as intended.

3. Orthogonal Array Testing

Orthogonal array testing is a software testing technique used to reduce test cases without reducing the test coverage. Orthogonal array testing is also known as Orthogonal array method (OAM), Orthogonal array testing method (OATM), and Orthogonal test set.

What are the benefits of gray box penetration testing?

1. Insider Information: Gray box testing is a perfect blend of black-box testing with knowledge of specific internal structures (or “inside knowledge”) of the item being tested. This inside knowledge could be available to the tester in the form of design documentation or code.

2. Less time consuming: With insider knowledge, testers can plan and prioritize the testing, which will take less than planning test cases with no understanding of the network or codebase.

3. Non-intrusive and unbiased: Gray box test, which is also called non-intrusive and fair. It is said to be the best way to analyze the system without the source code. The gray box test treats the application as a black box. The tester will know how program components interact with each other but not about the detailed program functions and operations.

How does gray box testing help secure your system?

Gray box penetration testing combines the best of black box and white box testing where the tester is provided with some knowledge of the application’s inner workings. In a typical black-box test, you don’t need to know anything about the application to find and verify the defects. This is to simulate how the actual user will experience the application. In a gray box test, you already know some information about the application, allowing the tester to act better on how the actual user will experience the application.

One of the best ways to test your defense is with an outsider threat. Let’s say you are protecting your environment with “standard” security controls. An outsider is anyway going to get in if they want to. So it doesn’t make sense to invest too much time or money in trying to stop an outsider that is motivated enough. Instead, you need to know how they will behave once they are in. And the best way to do this is with a gray box test.

Applying gray box penetration testing will help you secure your system from outside attacks and malicious insiders. In a gray box test, pentesters already know some information about the application, allowing them to simulate better how the actual user will experience the application. This means you will be able to test the application with a more extensive set of test cases, which will help you find errors, exploits, and security flaws before cybercriminals find them.

Why Gray box penetration testing is important?
Image: Why gray box penetration testing is important?

Why Astra’s Pentest Suite is a perfect fit for you?

All 3 types of penetration testing techniques have their own pros and cons but which one is perfect for you? Astra’s pentest suite is equipped with real-life hacking intelligence gathered from 1000+ vulnerability assessments and penetration tests (VAPT) done by our security experts on varied applications. 

Say NO to the old boring way to test your organization’s security. Astra’s Vulnerability Scanner is ever learning from new CVEs, bug bounty data & intelligence gathered from pentest we do for companies in varied industries. Your CXOs get a birds-eye view on the security posture of your organization with data-backed insights which help them make the right decisions.

In addition, to ensure utmost security We here at Astra believe in ‘proactive security’ measures where we anticipate the infiltration techniques used by hackers and recommend additional security countermeasures keeping your and your customer’s data secure.

Astra's Pentest Suite

Features of Astra’s pentest suite:

  • Self-served, on the cloud continuous scanner that runs 2500+ test cases covering OWASP, SANS, ISO, SOC, etc.
  • Rich and easy-to-understand dashboard with graphical representation that helps with vulnerability & patch management.
  • Developer & CXO level reporting.
  • Team collaboration options for assigning vulnerabilities for fix.
  • Multiple asset management under the same scan project.
  • Dedicated ‘Vulnerabilities’ section that offers insights on vulnerability impact, severity, CVSS score, potential loss (in $).
  • Comprehensive scanner that includes all the mandatory local and global compliance requirement checks.

It is one small security loophole v/s your entire website or web application

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1. What is gray box penetration testing?

Gray box pentesting refers to the approach where the pentester receives partial information about the system before the test.

2. What are the 5 stages of penetration testing?

The 5 stages of penetration testing are planning, information gathering and recon, scanning, exploitation, and reporting. Find out more on penetration testing guide

3. Why Gray Box Penetration Testing?

Gray box pentesting allows you to understand how much damage a user with limited privilege can cause.

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Keshav Malik

Meet Keshav Malik, a highly skilled and enthusiastic Security Engineer. Keshav has a passion for automation, hacking, and exploring different tools and technologies. With a love for finding innovative solutions to complex problems, Keshav is constantly seeking new opportunities to grow and improve as a professional. He is dedicated to staying ahead of the curve and is always on the lookout for the latest and greatest tools and technologies.

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