API SECURITY ASSESSMENT: Every request needs the right boundaries.
API security assessment examines whether an interface exposes records, functions or business actions to people and systems that should not have them. Testing goes beyond the application interface to challenge authentication, permissions, input handling and sensitive workflows through requests made directly to the API.
- Discipline
- Cyber Defense
- Engagement type
- Assessment
A valid token does not make every request legitimate.
An authenticated caller may still request another customer's record, modify a field their role should not control or automate a workflow beyond its intended use. API testing examines those permissions and assumptions at the service level.
Common triggers
opening an API to partners; launching a multi-tenant product; introducing new roles or integrations; changes to tokens, gateways or service identities.
Examine access at each level.
Records
Can a caller retrieve or change objects belonging to a different account, user or tenant?
Properties
Can a request expose or modify fields the caller should not control?
Functions
Are administrative and sensitive operations restricted independently of the client interface?
Business flows
Can legitimate operations be combined or repeated to misuse approvals, balances, invitations or other sensitive processes?
Resources and integrations
Do requests respect agreed limits, and are responses from connected services handled with appropriate trust?
Exposed interfaces
Are versions and endpoints understood well enough to define the assessment's coverage?
Test the relationships your documentation is meant to describe.
Specifications, sample requests and accounts with different roles help establish how the API should work. We compare that intention with observed behaviour. Findings include affected endpoints, caller conditions, request and response evidence and corrective guidance suitable for engineering review.
What you receive
An endpoint and role coverage record.
Request-level evidence connecting each finding to its access or workflow boundary.
Corrective actions for relevant service-side checks and configurations.
Can you assess an API without a user interface?
Yes. The API can be assessed directly. Documentation and representative access help establish the intended operations and permission model.
Is rate limiting the same as a load test?
No. Security testing can examine whether sensitive operations have appropriate limits. Measuring throughput and resilience under load is a separate activity with its own methods and operating conditions.
Will every endpoint be tested?
The endpoint set, API versions and depth are defined in scope. The report should make coverage and any limitations clear.
Which callers should be able to do what?
Share the API's purpose, consumers and permission model. We can help translate those relationships into a testing scope.
Related services: Web Application Security Testing and Source Code Review.