Software Testing – White Box Penetration Testing

Penetration testing refers to the authorized security attacks that are performed on your system to identify the security vulnerabilities and then resolve these security issues.

What is White-Box Penetration Testing?

White box penetration testing is also known by names like transparent box testing, clear box testing crystal, or oblique box testing. As the name transparent box testing suggests, the penetration testers have full access to the internal structure of the system.

1. The penetration testers have access to in-depth knowledge of the interior configuration of a system. 
2. They examine the security vulnerabilities of software. 
3. The white box penetration testing is conducted to identify and eliminate the problems, which can lead to a data breach.
4. A thorough inspection of the internal core system saves it from getting hacked and identifying the internal errors beforehand. 
5. It helps strengthen security and enhances usability.

Reasons For White-Box Penetration Testing

Unlike other components of penetration testing, white box penetration testing deals with all the valuable internal data. 

1. Extensive evaluation: It offers a high-level, extensive evaluation of valuable areas in the system.
2. Verification of Internal and External Configurations: It makes sure that the internal and external configuration of the system is working properly.
3. Identification of Security Vulnerabilities: It identifies the security vulnerabilities and makes sure that the spammers do not take advantage of them. 
4. Saving Data Breach: It focuses on the critical parts of the software to save the system from a data breach.

When Is White-Box Penetration Testing Necessary?

White box penetration testing is majorly required at 2 times 

1. Before software development: Developers conduct testing at this stage as testing at this stage is better as all changes can be made, as necessary, there and then.
2. After software development and before release: Before the launch of a software system developer tests the software to detect any defects.
3. After software release: Periodic check of launched software system means regular basis(at least once a year). Testing is carried out to detect any internal errors and fix any system defects that may compromise user security.

White-Box Testing vs Gray-Box Testing

Parameters	White-Box Penetration Testing	Gray-Box Penetration Testing
Knowledge	Complete access to organization infrastructure.	Somewhat knowledge of internal software systems is required.
Known as	It is also known as clear box testing.	It is also known as translucent testing.
Test	In white-box testing, the functionality is tested.	In gray box testing, the structure is tested.
Programming Language	White-box testing requires a high understanding of programming language.	It requires a partial understanding of programming language.
People Involved	White-box testing is done by the internal development team of the organization.	This is performed by third-party services. Developers and testers may or may not be involved in this testing.
Module Check	In this testing lower modules of the application are checked.	In this testing, the upper modules of the application are checked.
Algorithm Testing	It is suited for algorithm testing.	It is not suited for algorithm testing.

Various Techniques of White-Box Penetration Testing

The main aim of conducting white box penetration testing is to eliminate the security vulnerabilities of the system. It helps in strengthening the security and increases the usability of the code coverage analysis. Here are some of the ways which can help in code coverage analysis:

1. Statement coverage: The statement coverage tests all the programming statements. 
2. Path Coverage: The testing of the paths is the most critical technique in white box penetration testing. The white box analyses all the paths of the system to make sure there is no error. 
3. Branch Coverage: The penetration testers make sure that all the branches of the system are tested properly.
4. Decision Coverage: It is a form of White Box Testing where all the branches are tested properly. It results True or False of each Boolean expression of the source code. 
5. Control Flow Testing: It is a type of structural testing that comes under White Box testing. It determines the execution order of the statements or instructions given.
6. Multiple Condition Coverage: It is also called Condition Combination Coverage in which for a decision all the combinations of conditions need to be evaluated.
7. Data Flow Testing: It is a type of structural testing in which data, variables, and their values are focused mainly on when variables receive their values and where it gets used.
8. Condition Coverage: It is a type of white box testing technique which is also called Predicate Coverage. It checks for a Boolean expression and decides to evaluate it as True or False.

Steps In White-Box Penetration Testing

The below figure illustrates the steps involved in white box testing:

Steps involved in white box Penetration Testing

1. Understand tools and technologies used: Select the area that you want to test, and understand clearly the languages, tools, and technologies used for development.
2. Understand the source code: Check the code properly that you want to test, and understand that portion of code clearly and how it works.
3. Write test cases: Write test cases by keeping the vulnerabilities in mind means to which vulnerabilities you are targeting and how you will test that.
4. Execute test cases: Then test all the scenarios which you had identified till you get the root of the vulnerability.
5. Analyze and record results: As the final step analyze your findings and plan for resolutions. Then implement the solutions accordingly to avoid the issues.

Advantages Of White-Box Penetration Testing

Here are some of the advantages of using white-box penetration testing:

1. Time Saver: White box penetration testing saves time for the penetration testers. Because the testers already have in-depth information about the internal systems in the software.
2. Clear Nature: The white box penetration testing has another name called transparent box testing. As the name implies, white box penetration testing has clear box quality. Hence, it is easy to conduct any test with it.
3. Easy Error Detection: The white box penetration testing is done on the critical, internal architecture of the software. Hence, a tester can easily detect any errors or bugs in the system.
4. Easy Automation: Ethical hackers can easily conduct unit tests. The unit test performs operations on small, individual parts. If any small unit of the software has recently got broken then this penetration testing detects and helps.

Disadvantages Of White-Box Penetration Testing

Here are some of the disadvantages of using white-box penetration testing:

1. Requires in-depth knowledge of the system: As we know white box penetration testing is focused on in-depth knowledge of the system. Hence, the penetration testers will have a plethora of information about the core parts of the system. And this abundance of information can lead the testers in different directions than the hackers.
2. Expensive test: White box penetration testing is very expensive as compared to the other parts of penetration testing.
3. Requires extensive programming: The codebase in white box penetration testing keeps changing. Hence, sometimes, the core designs of the system may need redesigning and rewriting. White box penetration testing needs extensive programming.
4. Time Taking Test: As white box penetration testing works on the internal configuration and there is an abundance of information to deal with. Hence, it makes it a slow process.

Tools For White-Box Penetration Testing

Here are some of the tools which perform white-box penetration testing:

1. John the Ripper

John the Ripper tool is a password security auditing and password recovery tool originally developed for Unix operating system but now runs on multiple operating systems. 

Features:

1. It is an open-source password-cracking software tool.
2. It can run on any OS like Unix, macOS, Windows, DOS, etc.
3. It is a free-to-use tool.
4. You can do vulnerability analysis and test for other areas of penetration as well.

2. JUnit

JUnit testing tool used for unit testing Java source code, which acts as a very important tool in case of Test Driven Development.

Features:

1. It is an open-source framework.
2. It allows writing code faster with unit testing ensuring quality.
3. It uses a Test runner for executing the test cases.
4. Annotations in Junit are used for running the test methods.

3. NUnit

NUnit is an open-source testing tool used for unit testing of .NET and Mono. It works similar to the JUnit which is used for the Java language.

Features:

1. It is an open-source tool.
2. It provides Visual Studio support through a test adapter.
3. It supports tests organized as Multiple Assemblies.
4. It uses annotations to speed up test development and execution.

4. Metasploit:

Metasploit is an open-source testing tool mainly used to perform vulnerability tests associated with networks and servers.

Features:

1. It is an open-source framework.
2. You can verify vulnerability mitigations & manage security assessments.
3. It provides many exploitation tools for privilege escalation, packet sniffing, keyloggers, screen capture, etc.
4. It provides friendly GUI and third-party interfaces for penetration testing.