Penetration Testing: Automated v. Manual

Previously, we have thoroughly discussed what penetration testing is and how it is different from a vulnerability assessment, along with discussing penetration testing for SaaS companies as well as cloud infrastructure. Over the years, many service providers have started offering penetration testing as a service and it is a tedious process for the decision-makers of a business to choose an appropriate vendor. Penetration testing as a service is offered in many forms such as web application penetration testing application penetration testing,network penetration testing cloud penetration testing ,IoT penetration testing etc. Moreover, with organizations’ development strategy shifting towards CI/CD environments,penetration tests need to be conducted at DevOps speed. In this post, we will see the differences and benefits of automated and manual penetration testing methodologies and which is a better methodology.
Without a doubt, penetration tests play a vital role in the security of an organization’s technical infrastructure. Whether manual or automated tests should be conducted presents a big dilemma for the decision-makers. There can be many driving factors for an organization to select any one methodology, but it must be understood that each of these methodologies has its own benefits.

Automated Penetration Testing Benefits

Figure 1: Automated Penetration Testing Benefits

1. Coverage: Let’s consider that an organization has 10,000 assets spread across 25 locations. It will be harder for manual testing to cover all these assets due to various obvious reasons, such as skills, time, etc. On the other hand, automated tools can efficiently conduct penetration tests on these assets with minimal human intervention. For example, a tester performs manual crawling and then guides an automated tool by defining the scope of what needs to be scanned.
2. Speed: It is safe to say that automated tools work way faster. While conducting a penetration test, completing a manual penetration testing exercise will take more time than the time required by automated tools. Specifically, in environments like DevOps, where time is of the essence, automated tools help your team significantly cut down the time required to perform penetration tests.
3. Number of tests: Automated tools can be instructed to test a target for various types of attacks using hundreds or thousands of payloads in a single go. Manually, it will be a time-consuming process for either an individual tester or a team of testers. With automated tools in action, more breadth can be covered with minimum resource utilization.
4. Skill Set Required: This is a well-known fact in the cybersecurity community that it is hard to find skilled testers who have an attacker-like mindset to conduct a penetration test. Hence, it becomes a necessity for organizations to look out for a third-party service provider. However, automated tools are really easy to use and relatively quite easier than doing a manual penetration testing activity.
5. Reporting: An automated tool is designed in such a way that it is able to present its findings in the form of a well-structured report at the stroke of just one click. In addition, many automated tools allow testers to customize their report using various options. Documenting the report of a manual test may take hours while the same is not the case with automated tools.

Manual Penetration Testing Benefits

Figure 2: Manual Penetration Testing Benefits

1. Business Logic and Context: Automated tools come with a set of pre-defined rules, and hence, they fail to consider the vulnerabilities in the context of an organization and its business logic. Two organizations belonging to two different business domains will not have the same type of risks. Therefore, manual testing triumphs over automated testing when it comes to testing in the context of an organization.
2. Knowledge Base Updates: When there is either a new vulnerability or an exploit is released, you will be required to wait until they are updated in a tool’s knowledge base in the next update. On the other hand, a skilled tester can quickly learn about the new vulnerability or exploit in a day or two and implement it at the earliest, instead of waiting for the tool developers to update their database.
3. False Positives: For automated tools, the rate of false positive alerts being generated is on the higher side. These alerts are then required to be verified using manual testing activities.

So, which one is better: Automated v. Manual?

As we have seen, automated testing, as well as manual testing, have their own benefits. An organization must not make a choice between these two, and it should rely on a mixed methodology to get the best results. When a large number of assets or payloads are covered, it is better to use automated tools in the information-gathering phase. After this, manual testing can be used to exploit the vulnerability in the Discovery phase.