API Pentest

Protect Your Interfaces

What are entry points for attackers on APIs?

APIs are interfaces that allow you to access application logic and data through targeted requests. They are used for web, desktop and mobile applications and work without a web browser or graphical user interface. These components are indispensable in today's software landscape and often process large amounts of sensitive data.

For hackers, APIs are therefore extremely attractive as they offer the possibility to read personal customer data, bank details or even company secrets.

To protect your APIs from such attacks, our security analysts conduct in-depth investigations of your API endpoints and their interactions. Through this, vulnerabilities in your APIs can be identified and fixed at an early stage.

Common vulnerabilities include:

  • Faulty validation of input and injection vulnerabilities (e.g. SQL Injection, Remote Code Execution)
  • Lack of access controls for endpoints
  • Misconfiguration of the web server and security parameters
  • Insecure file processing (Zipslip, arbitrary file upload)
  • Use of insecure and/or outdated software components

What is our approach to API Pentests?

Our pentests are conducted according to a standardized approach, which is enhanced by specific aspects for API Pentests:

The starting point for our pentests is always the API documentation, such as a Swagger UI, Postman collection, or WSDL file, as this specifies the individual endpoints and the expected message format. Our security analysts check each endpoint of the interfaces individually, following the OWASP Testing Guide and the most common security vulnerabilities in APIs (OWASP API Security Top 10).

Subsequently, a holistic analysis of the API is performed. By combining requests to different endpoints, logic errors and complex vulnerabilities are uncovered that are often missed by security scanners. In addition, the authentication methods used, such as JSON Web Tokens (JWTs), and the access rights of different user roles are evaluated to identify, for example, missing access restrictions.



What checks are included in an API Pentest?

The following checks, among others, are part of API Pentests:

  • Identification of undocumented endpoints using automated analysis techniques
  • Verification of configuration settings for the API and the web server
  • Identification of software components and comparison with already known vulnerabilities for those
  • Injection attacks
  • Verification of access rights for each individual endpoint
  • Analysis of authentication and authorization mechanisms
  • Review of file upload functionalities

Optionally, we analyze the interaction between APIs and web applications or apps. Our security analysts check whether the software correctly receives and processes the API data. This is important to uncover and fix potential vulnerabilities in time.

Are your systems protected against attackers?

We would be happy to advise you on your options for having your APIs checked by our security analysts. Just get in touch with us.

More Insights

Pentest: Our standardized approach

Pentest: Your benefits at a glance



Please contact us with any questions or queries.


Phone: +49 6102 8631-190
Email: sales@usd.de
Contact Form


Daniel Heyne
usd Team Lead Sales,
Security Consultant Pentest, OSCP, OSCE