04
5–10 working days

API Security Assessment

APIs carry more authority than your front-end ever exposes. We test them as a hostile client.

Overview

The attack surface no one tests properly

Nobody thinks of "only called by our own mobile app" as a public endpoint, which is exactly why it gets less scrutiny than it should — and why it's often carrying more authority than the front-end anyone actually looks at. CyberMindX approaches your API the way an outsider with no goodwill would: enumerating what's there, swapping IDs across every object and role, pushing past rate limits, and fuzzing the schema until something gives.

Object-level authorization failures have sat at the top of the industry's API risk lists for years running, and our engagements are built around finding them specifically — alongside JWT and OAuth review, mass-assignment testing, and whatever REST, GraphQL, or gRPC-specific checks your stack calls for.

Methodology

How we run an API engagement

01

Schema Walk & Endpoint Enumeration

If you have an OpenAPI or GraphQL schema, we start there. If you don't, we build the endpoint map ourselves through direct enumeration before testing begins.

02

Authentication Review

We check how tokens are signed and verified, whether the OAuth flow can be manipulated, how refresh tokens rotate, and whether MFA is actually enforced at the API itself, not just the login screen.

03

Authorization Sweep

For every type of object your API handles, we set up two separate users in two separate tenants and try swapping their IDs across every endpoint that touches that data — systematically, not spot-checked.

04

Business Logic & Abuse Testing

We test whether rate limits and anti-automation controls hold under real pressure, and look for logic flaws — race conditions, promo abuse, and similar — that only surface when the API is used the "wrong" way.

05

Reporting & Free Retest

Every finding comes with a replayable request so your team can see it fire, plus suggestions for CI checks that would catch a regression before it ships again — and a free retest once you've patched.

What We Cover

Scope of testing

  • OWASP API Security Top 10-aligned testing
  • Broken object-level authorization (BOLA / IDOR) sweeps
  • Broken function-level authorization across roles
  • Schema introspection and over-permissive GraphQL queries
  • JWT / OAuth / OIDC implementation review
  • Rate-limit, quota, and resource-exhaustion abuse
  • Mass assignment, parameter tampering, injection
Common Vulnerability Classes

What we find most often

Ownership that's assumed, not checked

An endpoint takes an ID and trusts that whoever sent it is allowed to see or change that record — no actual ownership check behind it. This turns up again and again, even on APIs that have supposedly been reviewed before.

Token validation that isn't quite right

The obvious signing bugs are mostly gone, but subtler implementation mistakes — how the algorithm is verified, how the signing key is handled — still let a token be forged or recovered.

Fields nobody meant to expose

An endpoint accepts a JSON body and writes it straight to the database record, including fields — role, tenant, admin flag — that a user was never supposed to be able to set themselves.

Limits that don't hold up under load

Rate limiting that works in a demo but falls apart across multiple servers, or a per-IP limit that's trivial to route around, leaving the underlying business logic exposed to abuse.

Industries Served

Sector-aware testing

Enterprise IT & SaaS Media & Entertainment Healthcare Financial Services Engineering & Manufacturing Government & Public Sector
Deliverables

What you get

01 · Endpoint Coverage Map

Full authorization-matrix testing documented across every object type and role.

02 · Reproducible Findings

Per-finding reproduction you can replay directly against your API.

03 · CI Gate Suggestions

Recommendations for regression tests so the same bug class doesn't ship twice.

Typical Duration

5–10 working days, depending on endpoint count and role complexity.

What We Need From You

OpenAPI or GraphQL schema, and test users for each role.

Pricing & Retest

[Add your starting price] · free retest included

FAQ

Buyer questions, answered honestly

REST, GraphQL, or both?

Either or both — the methodology adapts to your API architecture, including mixed REST/GraphQL environments.

Do you require an OpenAPI / GraphQL schema?

It helps and speeds up testing, but isn't required — we can enumerate the surface manually where no schema exists.

Is mass assignment tested?

Yes, as a standard part of every API engagement.

Do you test JWT and OAuth?

Yes — signature validation, algorithm handling, token expiry, and refresh-flow integrity are all in scope.

Can we point you at a staging backend?

Yes, provided it's representative of production configuration and data model.

Ready to scope this engagement?

We'll align on goals, rules of engagement, and timeline within one working day.

Schedule Audit