What is API Penetration Testing?

In the digital era, Application Programming Interfaces (APIs) have assumed a pivotal role, acting as catalysts for the rapid advancement of software and application development within DevOps teams. Their significance lies in the unparalleled acceleration they bring to these processes. APIs not only streamline development efforts but also yield substantial time savings, and enhance the scalability and adaptability of systems, all while keeping development costs in check. Furthermore, APIs significantly expedite the time it takes to bring products to market, fostering agility and competitiveness.

In this article, we’ll cover the essentials of an API, API penetration testing, and how pentesting can help developers implement secure coding practices, thorough input validation, and robust authentication and authorization mechanisms.

What is an API?

An API, which stands for Application Programming Interface, is indeed a set of rules, protocols, and tools that allow different software applications to communicate with and interact with each other. It serves as an intermediary that enables two different software systems to understand each other and work together seamlessly.

What is an API Penetration Test?

There are many types of APIs but essentially API penetration testing is a penetration testing exercise performed by certified pentesters in a controlled environment simulating a real-world attack on an API.

API pentest is always initiated with a clear objective in place. Some of the most common reasons an organization may initiate API penetration testing are compliance requirements (SOC 2, HIPAA, GDPR, ISO 27001, PCI DSS, etc.), vendor assessments of third-party security requirements which are often needed to ensure that you’re a secure IT ecosystem for your clients, partners, vendors, and overall organization.

With a trusted API penetration testing service provider, an organization can securely and safely scan an API for vulnerabilities. A trusted API pentesting vendor will have pentesters with relevant certifications, like the OSCP, CEH, OSCE, CREST, CISSP, or GSNA. Benefits will include expert remediation guidance and customer support to formulate a risk remediation plan that builds cyber resiliency and improves overall security posture.

How is an API Pentest Conducted?

An API penetration test is conducted by simulating real-world attacks on an API to identify vulnerabilities. The test typically involves sending various requests to the API, analyzing the responses, and identifying any weaknesses or security flaws. The tester may also use automated tools to help identify vulnerabilities and simulate attacks. The goal of the test is to help identify and prioritize vulnerabilities, so they can be fixed before they can be exploited by adversaries.

During the scoping part of the pentest engagement, a project manager will work with an organization to understand their testing requirements, design the attack surface, and outline a plan of real-world API attack paths that a potential hacker would execute. This helps to determine how the pentester will conduct API penetration testing. API vulnerabilities will be identified, assessed, and prioritized for remediation based on a risk profile.
Throughout the API penetration testing exercises, the guidance provided by the OWASP API Security Project is invaluable. This guidance aids in the identification of vulnerabilities that are well-known and easily exploitable, as well as those more complex weaknesses present in the API. The following are the OWASP top 10 API risks in 2023.

• API1:2023 – Broken Object Level Authorization
• API2:2023 – Broken Authentication
• API3:2023 – Broken Object Property Level Authorization
• API4:2023 – Unrestricted Resource Consumption
• API5:2023 – Broken Function Level Authorization
• API6:2023 – Unrestricted Access to Sensitive Business Flows
• API7:2023 – Server-Side Request Forgery
• API8:2023 – Security Misconfiguration
• API9:2023 – Improper Inventory Management
• API10:2023 – Unsafe Consumption of APIs

What Vulnerabilities Does API Penetration Testing Uncover?

The most common vulnerabilities listed in the OWASP API Top 10 offer a great start for an API pentest, but that is just the beginning. Penetration testers should test for more than those ten vulnerabilities. However, sometimes API pentest engagements will go beyond the typical use case scenarios to include an expanded attack surface to identify both known and unknown vulnerabilities.

In BreachLock’s 2024 Penetration Testing Intelligence Report, over 3000 penetration tests were conducted between 2022 to 2023. Based on anonymized aggregated data, the most common critical and high-risk vulnerabilities discovered in APIs were domain email spoofing, Apache HTTP server byte range DoS, and sensitive data exposure.

Penetration Testing of APIs Across the Software Development Life Cycle (SDLC)

Penetration testing of APIs across the Software Development Lifecycle (SDLC) includes various stages of software development and deployment. And, as we have established, APIs are a set of rules and protocols that allow different software applications to communicate with each other. They enable developers to access certain features or data of a software system without needing to understand its internal workings.

It is crucial to understand the strong connections between APIs and SDLC, and the effectiveness of pentesting across all phases from development through post-deployment.

API Development and Security: During the development phase of the SDLC, APIs are often created to enable different components of a software system to communicate. Proper design and implementation of APIs are crucial for ensuring security. Pentesting can be performed on these APIs to identify potential security vulnerabilities, such as injection attacks, improper authorization, or data exposure.

SDLC Security Integration: Security should be integrated into every phase of the SDLC to ensure that potential vulnerabilities are identified and mitigated early on. Pentesting can be conducted at various stages of the SDLC, such as during the testing phase, to uncover security weaknesses before deployment.

Post-Deployment Testing: After a software system is deployed, APIs are often used to interact with the system. Pentesting can be used to assess the security of these APIs, checking for vulnerabilities that might have been missed during earlier stages of development.

Ongoing Security Assessment: As part of the maintenance phase of the SDLC, regular pentesting should be performed to ensure that the software remains secure over time, especially as new features are added, and changes are made.

In summary, APIs and SDLC are interconnected with pentesting as part of a holistic approach to software security. Proper development practices, security integration throughout the SDLC, and regular pentesting help identify and address vulnerabilities, reducing the risk of security breaches and enhancing the overall security posture of a software system.

How Long Does API Pentesting Take?

Part of the answer to this question is that the lead time for API penetration testing depends entirely on the scope of the project. For API penetration testing specifically, the scope is determined by the number of APIs that are to be tested. As you’d assume, the more APIs that need to be assessed, the longer the API penetration testing engagement will take. However, some generalizations can be made about the lead time when choosing your penetration testing provider.

Traditionally, API penetration testing followed a completely manual and consultative approach, a process that could take conventional testing providers several months. However, with BreachLock’s PTaaS model, you can initiate your API pentesting within 24 hours. Results from your pentesting engagement are available in real-time through the BreachLock platform, and evidence-based, audit-ready reports are made available once vulnerabilities are remediated and an “all clear” has been established. Reporting is dependent upon key findings, the number of vulnerabilities that were identified, and the time needed to prioritize these for remediation. Technical reports are available for auditors, which include more in-depth vulnerability details, while an Executive Report is available for an organization’s executives and Board members.

BreachLock API Penetration Testing Solutions for Your Security Needs

In the face of today’s expanding threat landscape, it is imperative to subject your APIs to rigorous security testing to identify vulnerabilities that could potentially jeopardize your digitally connected ecosystem, user base, and data integrity. BreachLock employs both automated and human-delivered pentesting solutions for API security assessments, resulting in enhanced API security.

With BreachLock’s PTaaS, organizations can initiate regular API penetration testing within a single day, receive comprehensive findings within 7-10 days, and promptly initiate critical risk mitigation measures Our certified experts harness state-of-the-art tools and methodologies to discern and remediate vulnerabilities effectively, ensuring the continual security and compliance of your organization.
Experience the advantages of collaborating with the premier penetration testing as a service provider that places paramount importance on customer success.

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