API Penetration Testing
API penetration testing is a manual, expert-led assessment of your REST and GraphQL APIs that finds and safely exploits flaws before attackers do. We focus on the risks that matter most — broken object- and function-level authorization (BOLA/BFLA), authentication and JWT weaknesses, excessive data exposure, injection, and rate-limiting — and deliver a risk-rated report, remediation guidance, and a free retest.
The OWASP API Top 10 — in plain language
The flaws that most often lead to API breaches.
Broken object-level authorization (BOLA)
The number-one API risk: swapping an ID in a request to read or modify another user's data. We probe every object reference for missing ownership checks.
Broken function-level authorization (BFLA)
Standard users reaching admin-only or privileged endpoints. We test whether role and function boundaries actually hold across your API.
Authentication & JWT flaws
Weak token handling, missing signature validation, algorithm-confusion, replay, and broken session logic that let attackers forge or hijack identities.
Excessive data exposure & injection
APIs that over-return fields and trust the client to filter them, plus SQL, NoSQL, and command injection reachable through API parameters.
Rate limiting & resource abuse
Missing throttling that enables credential stuffing, enumeration, and denial-of-wallet — where unbounded requests run up cost or take services down.
GraphQL introspection & abuse
Exposed introspection, deeply nested query abuse, batching attacks, and field-level authorization gaps specific to GraphQL APIs.
A proven, OWASP API-aligned process
Scope
We agree endpoints, roles, test accounts, and rules of engagement — and collect your API docs, schema, or collection to test comprehensively.
Map & enumerate
We map every endpoint, method, parameter, and role — including undocumented and hidden routes — to understand the full API surface.
Manual testing
Aligned to the OWASP API Security Top 10, we test authorization, authentication, injection, and data exposure across REST and GraphQL.
Safe exploitation
We prove real impact by chaining authorization flaws and abusing tokens — showing exactly what an attacker could reach — without harming production.
Report
A clear report with an executive summary, risk-rated findings, request/response evidence, and step-by-step remediation for your engineers.
Retest
After you remediate, we retest the findings and confirm closure — evidence you can share with auditors and customers.
Deliverables that drive action
Professional report
Every finding documented with request/response proof-of-concept, affected endpoints, and reproduction steps, plus a plain-language executive summary.
Remediation guidance
Developer-ready fixes for each finding — authorization checks, token hardening, schema and rate-limit changes — not just a list of problems.
Free retest & attestation
We re-verify remediated findings and provide a letter of attestation you can share with customers, partners, and auditors.
Related testing
For continuous automated API and app assessment between engagements, explore Faseel Suite.
API pentesting, explained
Secure your APIs before attackers probe them
Book a manual API pentest for your REST and GraphQL endpoints, or automate assessment with Suite.
