Application Security
API Security Testing
Specialized penetration testing for REST, GraphQL, and gRPC APIs — built around the OWASP API Security Top 10 and the authorization and business-logic flaws scanners miss.
Overview
APIs are now the primary attack surface for modern apps — and the most common breaches come from authorization flaws like BOLA/IDOR that automated scanners cannot reliably find. Testing an API well requires understanding intent: which object belongs to which user, which action each role may perform, and where the business logic can be abused.
We test every endpoint, method, and role combination by hand, validating object- and function-level authorization, token handling, input validation, and data exposure. You get a prioritized report mapped to the OWASP API Security Top 10 with reproducible proof and remediation guidance.
Typical engagement: 2–8 weeks, depending on scope, access, and reporting requirements.
What we test
Broken Object Level Auth (BOLA/IDOR)
The #1 API risk: we attempt cross-tenant and cross-user object access on every resource and identifier.
Broken Authentication
Token forgery, weak JWT validation, session fixation, credential stuffing exposure, and OAuth/OIDC flaws.
Excessive Data Exposure
Endpoints returning more than the UI needs, verbose errors, and sensitive fields leaking in responses.
Function Level Authorization
Role and privilege escalation across admin and privileged endpoints (BFLA), including hidden methods.
Mass Assignment & Injection
Over-permissive object binding, plus SQL/NoSQL, command, and SSRF injection across parameters.
GraphQL & Rate Limiting
Introspection abuse, nested-query DoS, batching attacks, and missing rate limits or resource controls.
How the engagement runs
- 1
Inventory & Spec
Map every endpoint from OpenAPI/GraphQL schemas, traffic, and discovery — including shadow APIs.
- 2
Auth Modeling
Document roles, scopes, and object ownership to drive authorization test cases.
- 3
Manual Testing
Per-endpoint, per-role exploitation against the OWASP API Security Top 10.
- 4
Report & Retest
Prioritized findings with proof-of-concept requests — and a free retest after fixes.
Common questions
- Why do APIs need testing separate from a web app pentest?
- API risks are dominated by authorization and business-logic flaws (like BOLA) that depend on understanding object ownership and roles. A dedicated API test exercises every endpoint and role combination directly, rather than only what the UI exposes — coverage a standard web pentest often misses.
- Do you test REST, GraphQL, and gRPC?
- Yes. We test REST/JSON, GraphQL (including introspection, batching, and nested-query abuse), and gRPC/Protobuf services, adapting tooling and techniques to each protocol.
- What do you need from us to start?
- Ideally an OpenAPI/Swagger or GraphQL schema, a staging endpoint, and test accounts for each role. We can also work from captured traffic or a Postman collection if no spec exists.
- Which standards does the assessment follow?
- Testing is built around the OWASP API Security Top 10 and OWASP ASVS, and maps cleanly to SOC 2, ISO 27001, and PCI DSS requirements.
- Can you test APIs in CI/CD or pre-release?
- Yes. We can run focused API assessments against release candidates and integrate authenticated checks into your pipeline so regressions are caught before they ship.
Find the gaps before attackers do.
Get a tailored scope and fixed quote for api security testing on a 15-minute call.