API security

API Security Testing for Fintech, SaaS, and Startup Backends

Review the backend behavior that powers mobile apps, dashboards, integrations, accounts, payments, and customer data.

Get a Free External Security Assessment View Methodology

Share an asset you own or are authorized to test. Public validation comes first; deeper checks require signed scope.

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Direct answer

What is API security testing?

API security testing reviews endpoints, authentication, authorization, object access, data handling, rate limits, and business logic. It helps teams find issues that may not be visible in the user interface but can affect customer data or critical workflows.

Access control and data exposure focusUseful for fintech, SaaS, and mobile appsManual validation available where needed

What this covers

API Security Testing

High-risk API areas

Kintsubyte focuses on broken object access, role bypass, excessive data exposure, weak rate limiting, token handling, and sensitive business workflows.

Inputs that help

API documentation, endpoint collections, test accounts, role descriptions, and sensitive workflow notes make testing safer and more useful.

Next step

Need an external assessment?

Share an owned or authorized asset. Kintsubyte starts with non-destructive public checks, then scopes remediation, retesting, or deeper signed review only where useful.

Get a Free External Security Assessment View Services

Contact Kintsubyte

Request a free external assessment.

Send the company, asset URL, and scope context. Kintsubyte will review public exposure where authorization is clear and reply with confirmed findings or recommended scope.

bolarinwa@kintsubyte.comNigeria-based, remote-first across AfricaWe only test systems you own or are authorized to test