API Security Testing (API VAPT)
APIs power your apps, partners and integrations — and they’re now the most attacked part of most modern platforms. Because APIs expose business logic directly, a single broken authorisation check can leak every customer’s data. Aesparrow’s API Security Testing (API VAPT) is built around the OWASP API Security Top 10 and goes deep on the flaws automated tools consistently miss: broken object-level authorisation (BOLA/IDOR), mass assignment, and business-logic abuse.
We test REST, GraphQL and SOAP APIs the way an attacker would — enumerating objects, tampering with tokens, and chaining authorisation gaps into real impact. Using your Swagger/OpenAPI definitions (or discovering endpoints ourselves), we validate authentication, authorisation, rate limiting and data exposure across every route, then hand you verified, developer-ready findings and re-test the fixes for free.
API Security Testing (API VAPT) — done right, the first time.
Senior practitioners. Verified findings. Free re-test.
Overview
API Security Testing is an authorised, in-depth assessment of your API layer — authentication, authorisation, input handling, rate limiting and business logic. Because APIs expose data and functionality directly, small authorisation gaps can have outsized impact. We combine endpoint discovery, token and session analysis, and manual exploitation to find and prove the issues that matter.
What we test for
Built around the OWASP API Security Top 10 and the realities of modern API design.
- Broken Object Level Authorisation (BOLA/IDOR) — the #1 API risk
- Broken authentication — weak JWT/OAuth flows, token handling
- Broken function level authorisation — admin actions exposed to users
- Mass assignment — over-permissive object binding
- Excessive data exposure — over-returning sensitive fields
- Lack of rate limiting — and resource exhaustion
- Injection & SSRF — across parameters and payloads
- Business logic abuse — workflow and pricing manipulation
- Security misconfiguration — CORS, verbose errors, gateway rules
- GraphQL-specific issues — introspection, batching, deep queries
Our testing methodology
Discovery & spec review
We ingest Swagger/OpenAPI or enumerate endpoints, roles and auth flows.
Authentication analysis
JWT, OAuth 2.0 and session tokens examined for weaknesses and bypass.
Authorisation testing
Systematic BOLA/BFLA testing across objects, roles and tenants.
Manual exploitation
We chain findings into real impact — data access, privilege escalation.
Reporting & triage
Verified findings with CVSS, evidence and remediation guidance.
Remediation re-test
Fixes verified and the report updated at no extra cost.
Framework mapping
- OWASP API Security Top 10 — the API-specific risk baseline
- OWASP ASVS — verification requirements for API controls
- NIST SP 800-115 — technical assessment methodology
- MITRE ATT&CK — techniques for adversary-style testing
Deliverables
Executive summary
API risk posture and priorities for leadership.
Technical findings
Endpoint, request/response evidence and root cause.
Risk ratings & CVSS
Impact-based severity you can act on.
Remediation guidance
Concrete fixes for your API and gateway config.
Re-test report
Verification that issues are genuinely resolved.
Compliance mapping
Evidence aligned to SOC 2, ISO 27001 and PCI DSS.
Why choose Aesparrow for API VAPT
OWASP API Top 10 depth
BOLA, mass assignment and function-level auth tested by hand.
REST, GraphQL & SOAP
Coverage across every API style your platform ships.
Auth & token expertise
JWT, OAuth 2.0 and session flows scrutinised end to end.
Free remediation re-test
We verify fixes and update the report so you can prove closure.
If your product is API-first, your security testing should be too. Talk to us about an API VAPT scoped to your endpoints, authentication model and release cadence.
Frequently Asked Questions
Do you test REST, GraphQL and SOAP APIs?+
Yes. We test all three, tailoring the approach to each — for example introspection, batching and deep-query abuse for GraphQL, and WSDL/operation review for SOAP.
Do you need our API documentation to test?+
It helps us go deeper faster — a Swagger/OpenAPI spec or Postman collection lets us cover every route. If you don’t have documentation, we can discover and enumerate endpoints ourselves.
What is BOLA and why does it matter so much?+
Broken Object Level Authorisation is when an API lets one user access another user’s data by changing an identifier. It is the most common and highest-impact API vulnerability, and it requires manual testing to find reliably — which is exactly what we do.
How do you handle authentication during testing?+
We work with you to obtain test accounts across roles and tenants so we can properly test authorisation boundaries, token handling and privilege escalation.
Is remediation re-testing included?+
Yes — once you have applied fixes we re-test them and issue an updated report confirming the risks are closed.
Ready to secure api security testing (api vapt)?
Book a free, no-obligation consultation with an Aesparrow practitioner. We’ll scope your needs, explain the approach, and share indicative timelines — no sales script.
Related services
Web Application VAPT
Your web application is the front door to your business — and the first thing an attacker probes. Aesparrow’s Web Application VAPT (Vulnerability Assessment and Penetration Testing) combines deep manual testing with trusted tooling to find the flaws that automated scanners miss: broken access control, business-logic abuse, injection, and authentication weaknesses. You get a clear, prioritised picture of what a real attacker could do, and exactly how to fix it before it costs you.
Red Team Assessment
A penetration test answers "is this system vulnerable?" A red team assessment answers a harder, more valuable question: "if a determined attacker targeted our business, would we detect and stop them?" Aesparrow’s red team runs a goal-based, adversary-style simulation across people, process and technology — emulating real threat actors to test your detection and response, not just your patch levels.
Mobile Application VAPT
Your mobile app runs on devices you do not control, which makes it a uniquely exposed part of your attack surface. Aesparrow’s Mobile Application VAPT tests Android and iOS apps against the OWASP Mobile Top 10 — covering insecure data storage, weak cryptography, broken authentication and the client-server APIs behind them — using both static and dynamic analysis on real devices.
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