Guide to Gray Box Penetration Testing

Many cybersecurity experts agree that the best way to understand cyber criminals is to simulate their attacks. With a strong penetration testing methodology, experts and their clients are clear on what vulnerabilities exist in the latter’s networks, API builds, and cybersecurity plans.

Gray box penetration testing, specifically, gives testers or ethical hackers partial knowledge of the services and systems they’re about to attack. This insider knowledge then, hypothetically, gives them enough knowledge about the best tools and ethical hacking strategies to use.

In this guide, we will explore what gray box testing looks like in practice, how it’s executed, and why it differs so much from black box and white box testing.

What is Gray Box Penetration Testing?

A gray box penetration test is a controlled security assessment where a penetration tester has limited knowledge about what a client’s infrastructure or system looks like.

This means they’re not quite testing systems blind, like a legitimate hacker, but can use this insider knowledge to their advantage.

Gray box penetration testing is widely regarded as one of the most efficient types of penetration testing, as it skillfully combines the advantages of both white box and black box methodologies.

Hackers still have to explore different types of attack vectors and the strength of a client’s cybersecurity posture, but they have at least some form of a roadmap in place.

Along with limited information about how client systems work, hackers running gray box pen testing are armed with various penetration testing tools that simulate typical cyberattacks.

Pen testers dive deep to spot potential vulnerabilities and then try different testing methods to try and break through security barriers. Gray box penetration testing may take place internally and externally, so business operators understand the risks on either side of their firewall.

Why choose Gray Box Penetration Testing?

Gray box penetration testing helps security experts closely understand the vulnerabilities that real-world attackers might be poised to exploit. With insider data, these testers are more privileged than malicious hackers in that they can explore every facet of a company’s infrastructure.

Gray box methodologies are considered the most efficient and the most cost-effective of all three box testing techniques.

Black box penetration testing takes place largely in the dark and might not find all the vulnerabilities that affect a company – while white box testing is time-consuming.

Many business owners choose the middle option, gray box, for the best of both worlds. That said, there are still benefits to the other types of pen tests – which might vary depending on your business’s specific needs.

How is Gray-Box Penetration Testing different from Black and White Box Penetration Testing?

Gray box penetration testing sites in the middle – a black box penetration test is conducted blind, much like a real-world attacker, while a white box penetration test offers testers complete knowledge of a client’s systems.

Black box security testing is as close to “real” hacking as you can get without it becoming hazardous. It’s a good option for assessing insider threats and external issues at speed. However, it’s a limited level of access that can leave a lot of potential vulnerabilities unexplored.

White box pen testing, therefore, goes in the opposite direction, and supplies hackers with absolutely everything they need to know. Of the three box testing techniques, this is the most comprehensive option with a complete level of access.

However, some feel that the full knowledge approach doesn’t mimic a real-life threat closely enough – which is why they lean toward gray box testing.

Gray box methods combine the semi real-world approach of black box testing while offering the extended scope of white box testing.

They might only have access to the source code, for example, but they can still derive useful information to help clients make their security more robust.

That said, those in favor of white box penetration testing might suggest that gray box tests don’t offer complete coverage – and that some flaws may still go unnoticed.

It’s why many gray box testers use some techniques and tricks that are unique to this specific type of assessment. That said, all pen testers follow similar methodologies and use common resources such as OWASP to target specific threats.

Gray Box Testing Techniques

To simulate an internal or external attack, hackers use various tools and techniques to sniff out security vulnerabilities and push boundaries. They also use tools to help with the authentication and validation of assumed threats affecting a target system.

Here are just a few typical techniques gray box testers use to exploit misconfigurations, functionality issues, security flaws, and more.

Matrix Testing

During matrix testing, hackers dig deep into the different variables of programs that clients use within an infrastructure. It is much like taking apart a physical device and checking each part works correctly – only, it’s with the code within specific software!

This is one of the most effective gray box testing methods for assessing specific platforms or web application setups. It’s a type of tinkering that allows testers to understand how certain code works, and what they could recommend to clients in terms of remediation (if flaws are spotted).

Regression Testing

Regression testing is used to find specific defects that might be present in changes made to software – it is, ultimately “retesting.” It’s typically used in software development to ensure that existing programs and features are still fit for purpose before shipping to the public.

Gray box testers can also use these techniques to assess whether or not any hidden side effects have arisen due to recent upgrades.

If there are any side effects, testers will report back to their clients to advise that their base products are suffering – and that new code adjustments are required.

Orthogonal Array Testing

Orthogonal Array Testing is otherwise known as OAT, and it’s a technique that helps testers to optimize the number of test cases deployed in line with overall test coverage and effort.

Specifically, it helps gray box testers to ascertain how many test cases they might need to pull the information they require. This helps to reduce time, effort, and overall cost – simply because testers don’t have to charge into blindly testing and instead have plans in place.

Pattern Testing

Pattern testing, last of all, is about looking at the history of specific code or software to see if there are any concerning trends or, indeed, patterns. This can help testers to build a more confident action plan.

Much like the other techniques listed above, this strategy delves into the inner workings of software to find flaws that could prove extremely harmful if hackers were to find them.

Conclusion

Ultimately, there are no right or wrong answers when it comes to choosing the right type of penetration testing technique. The best option for you will depend entirely on what you’re looking for from a security test (and the following advice).

Gray box penetration testing can cover enough ground for ethical hackers to spot potentially hazardous vulnerabilities that black box testing might miss. At the same time, it is more cost-effective and less time-consuming than white box testing, but it’s not as comprehensive.

If you’re unsure about what to expect from penetration testing and would like to know more about setting up a custom plan of attack from a leading cybersecurity team, get in touch with VikingCloud.

Our team of ethical hackers and security professionals are always ready to mimic the latest hacking techniques and to help you make your posture more secure.

Whether you’d like us to assess all your internal workings, a few outputs, or specifically your application security, we can help. Don’t leave your company’s data security lingering as a last-minute to-do on your list!