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Penetration Testing
Your APIs are the backbone of your product — and one of the most attacked surfaces on the internet. Broken authorisation, exposed endpoints, and missing rate limits can hand an attacker your entire customer dataset.
About This Service
Comprehensive security testing of your REST, SOAP, and GraphQL APIs to uncover authentication weaknesses, authorisation flaws, injection vulnerabilities, and business logic issues.
APIs are increasingly targeted because they sit at the boundary between your frontend, your backend, and third-party integrations — and are frequently deployed without the same security scrutiny applied to web applications.
OWASP API Security Top 10, OWASP Testing Guide
Typical Timeline: 3–7 days depending on API complexity and number of endpoints
Report: Executive summary + full technical findings
Retest: Complimentary, included in every engagement
NDA: Signed before any technical discussion
Deliverables
Overview of API security posture and key risk findings
All findings mapped to OWASP API Security Top 10 with endpoint references, proof-of-concept, and CVSS scores
Complete documented list of all discovered and tested endpoints
Endpoint-specific fix guidance written for backend developers
Confirms critical and high findings resolved after remediation
Scope
Authentication mechanisms — API keys, OAuth 2.0, JWT tokens
Authorisation and broken object-level authorisation (BOLA/IDOR)
Broken function-level authorisation
Injection vulnerabilities in API parameters
Sensitive data exposure in API responses
Rate limiting and resource consumption issues
Mass assignment and parameter tampering
API versioning and deprecated endpoint risks
GraphQL-specific attacks — introspection, batching, depth abuse
SSRF via API endpoints
Process
Every engagement follows a defined, transparent process — no surprises, no hidden scope changes, and no invoice for work you did not agree to.
Document all API endpoints, authentication flows, and roles.
Build a full inventory of endpoints, parameters, and data flows.
Attempt to bypass authentication and access controls.
Test all parameters for injection and logic flaws.
Findings mapped to OWASP API Security Top 10 with remediation guidance.
Verify that identified vulnerabilities have been fixed.
Why Us
Automated tools find known signatures. Our certified consultants find the chained attack paths, logic flaws, and context-specific vulnerabilities that no scanner will surface. Every finding we report is manually verified — zero false positives.
Every finding includes a proof-of-concept, a CVSS risk score, the affected system or endpoint, and step-by-step remediation guidance written for the team that has to fix it. Your developers and your board both get a report they can use.
We sign a formal NDA before any technical discussion begins. Your vulnerabilities, your architecture, and your engagement findings are treated with the same confidentiality as attorney-client communications. We have never disclosed client information.
Every engagement includes a complimentary retest once your team has addressed the findings. We verify that the vulnerabilities are genuinely closed — not surface-patched — and issue a formal retest certificate you can share with clients and auditors.
We don’t just run an OWASP API checklist. We map every endpoint, test access across all authentication states, and attempt to chain findings together. If one user can reach another user’s data through a single API call, we’ll find it.
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OWASP-aligned manual testing covering authentication, access control, and injection.
FAQ
We test REST, SOAP, GraphQL, and gRPC APIs. We work with both internal APIs and publicly exposed APIs.
Documentation helps, but it is not required. We can use traffic interception to map undocumented APIs. Providing documentation (Swagger/OpenAPI) allows for more thorough coverage.
It is the industry-standard list of the ten most critical API security risks, published by OWASP. Our testing methodology ensures full coverage of these risks on every engagement.
Yes. We work with you to set up test accounts with the required access levels to test each role and access tier.
Get a free scoping consultation — no commitment required. We’ll scope the right API security testing engagement for your environment and send a fixed-fee proposal within 24 hours.
