API Security Testing
Protect your APIs from abuse and data leakage
APIs fail differently from web applications. The interface is machine-readable, the authorisation surface is wide, and a single predictable object identifier can expose an entire customer table. We test REST, GraphQL, and WebSocket interfaces the way they are actually abused.
Scope
What the engagement covers
- REST, GraphQL, and WebSocket testing
- Token, authentication, and rate-limit validation
- Full OWASP API Top 10 coverage
- Broken object level authorisation (BOLA) detection
- Mass assignment and excessive data exposure testing
- API versioning and deprecated endpoint discovery
Outcomes
Why teams choose this
Authorisation first
BOLA, privilege escalation, and scope confusion are tested role by role, not sampled.
Every protocol
REST, GraphQL, gRPC, and WebSocket interfaces are all in scope as standard.
Abuse resistance
Rate limiting, quota enforcement, and resource exhaustion are validated under real load.
Undocumented endpoints
We discover the routes missing from your specification, then test those too.
Process
How we work
- 1API endpoint discovery and specification review
- 2Authentication mechanism testing
- 3Authorisation and access control validation
- 4Input validation and injection testing
- 5Rate limiting and quota testing
- 6Data exposure and privacy assessment
Deliverables
What you receive
- Endpoint inventory including undocumented routes
- Per-role authorisation matrix with tested outcomes
- Findings report with reproducible requests
- Postman or OpenAPI collection of proof-of-concept calls
Questions
Frequently asked
Do you need our OpenAPI specification?
It helps and speeds things up, but it is not required. We discover endpoints independently and routinely find live routes that specifications omit.
Do you test GraphQL specifically?
Yes, including introspection exposure, query depth and complexity limits, batching abuse, and field-level authorisation.
Related
Other services
Web Application Penetration Testing
Manual, exploit-verified testing across the OWASP Top 10 and your own business logic.
SAST – Static Application Security Testing
Source-level analysis wired into your pipeline, so flaws never reach a release branch.
DAST – Dynamic Application Security Testing
Authenticated scanning against the running system, including multi-step flows and APIs.