API penetration testing
API pentesting for authorization, data, and business logic
We investigate REST, GraphQL, and other interfaces at object, function, and workflow level, including undocumented paths.
The assessment tests how identity, data, and services connect in a realistic attack path, not only whether individual requests fail.
01 / Coverage
What we test
We confirm boundaries and critical journeys before testing so the work reflects your business risk.
Object authorization
BOLA/IDOR, mass assignment, and cross-tenant or cross-account access.
Identity and tokens
OAuth, JWT, API keys, refresh tokens, scopes, and credential lifecycle.
Business workflows
Limits, sequence, replay, operation state, and abuse of sensitive functions.
Data and integrations
Excessive data exposure, GraphQL, webhooks, SSRF, and service-to-service trust.
02 / Method
An assessment you can defend to engineers and auditors
We combine manual investigation, tooling, and evidence control. A specialist validates every reported finding.
- 01
Map the API
Correlate specifications, traffic, roles, versions, and undocumented endpoints.
- 02
Build an access matrix
Test objects and functions across users, roles, and organizations.
- 03
Explore abuse cases
Combine requests, states, and integrations into realistic attack scenarios.
- 04
Prove and retest
Capture minimum safe evidence, recommend controls, and validate remediation.
03 / Outputs
Material built for decisions and remediation
The report explains risk to leaders and gives engineers reproducible steps without scanner noise.
PENTEST.RED / API / 02
API risk matrix
Findings mapped to endpoints, roles, affected data, and business impact.
Reproducible requests
Safe HTTP or GraphQL examples with the conditions needed to reproduce.
Control guidance
Specific changes for authorization, validation, rate controls, and logging.
Retest and readout
Fix validation and a working session with the API engineering team.
Do you need an OpenAPI specification?
It speeds up coverage but is not required. We can map the API from traffic, client behavior, and available documentation.
Do you test GraphQL?
Yes. We review schema exposure, resolvers, field authorization, query complexity, and sensitive data access.
Do you assess OAuth and JWT?
Yes. We test issuance, validation, scopes, rotation, revocation, and trust between protocol participants.
Can you test only new endpoints?
Yes. A focused release assessment works when dependencies and risk boundaries are clearly defined.
Next step
Get a scoped assessment plan
Tell us about the system, timing, and reason for testing. We will clarify scope and recommend an engagement with no obligation.