Penetration tests often get classified as either “black box pentest”, “white box pentest”, or even “gray box pentest’. However, cutting through the jargon can be challenging. Read on to understand these different types of penetration testing and when each one should be used.
TLDR: A black box penetration test is where the tester has no knowledge of the system beforehand, whereas a white box penetration test is where the tester has full knowledge of the system.
What is a black box penetration test?
A black box penetration test is a security assessment of a system or application where the tester has no prior knowledge of the system. The aim of the test is emulating a real world scenario where outside attacker, who would typically not have access to proprietary knowledge beforehand including source code and architecture design docs, attempts find and exploit security vulnerabilities.
To carry out a black box penetration test, the tester will use a variety of tools and techniques to probe the system for vulnerabilities. These may include network scanning & enumeration, web application scanning & enumeration, and manual testing.
The advantages of black box testing include:
- It is useful in situations where the organization does not want to share internal information with the penetration tester such as commonly done in bug bounty programs.
- It is useful when organization wants to test its response to a real-world attack.
The disadvantages of black box penetration include:
- It is much more time consuming for testers to find vulnerabilities so this type of testing typically has a significantly lower return on investment for companies.
- It is much harder to detect certain vulnerabilities such as blind injection and tester may have to use fuzzing in certain cases to detect these types of vulnerabilities.
- It is difficult to adapt this type of testing for situation where testing individual functions or classes is needed such as during development.
As with all types of penetration testing, it is important to note that the test is only as good as the tester’s skills and knowledge. A tester with little experience may not be able to find all of the vulnerabilities in a system.
What is a white box penetration test?
A white box penetration test is an ethical hacking method used to assess the security of an organization’s IT infrastructure. The tester is given complete knowledge of the system before beginning the test.
Whitebox penetration testing includes source code assisted penetration testing, where a pentester uses knowledge of code to prove vulnerabilities.
The advantages of black box testing include:
- It typically has significantly higher return on investment for companies (i.e. more vulnerabilities found per dollar spent).
- It is easier to detect certain vulnerabilities such as blind injection as the tester can use code or other knowledge to detect or assist proving the existence of a vulnerability.
- It is easy to adapt this type of testing for situation where testing individual functions or classes is needed such as during development.
The disadvantages of black box penetration include:
- It is not useful in situations when an organization may not want to divulge information about the system(s) to the testers.
- Less realistic, as the penetration tester has more information than the typical attacker who has no knowledge of the system beforehand.
Is there something in between?
Yes: gray box penetration testing. A gray box penetration test is a type of security test where the tester has some but not all knowledge of the system before beginning the test. This might include information about the network architecture, application structure, and even some details about the code or not. The goal of a gray box test is to combine the advantages of both black box and white box testing. By having some knowledge of the system, the tester can create more targeted attacks and find more vulnerabilities. However, the tester doesn’t have complete knowledge of the system.
Which is better?
Neither is better than the other as they have different use-cases. Black box penetration testing is better suited for bug bounties and other situations where the insider information about the systems should not be shared with the testers or where a realistic attack scenario is needed. White box penetration testing is better suiter for situations where a company wants to assure that as many vulnerabilities as possible are found, and for security testing individual functions or classes such as during development.
Thanks for reading: Black Box vs Gray Box vs White Box Pentest
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