API Security Testing
Comprehensive security testing of REST, GraphQL, and SOAP APIs against OWASP API Top 10.
API Security Testing
Modern applications live and die by their APIs. REST endpoints, GraphQL schemas, gRPC services, and legacy SOAP interfaces expose business logic, data, and integrations that attackers target before anything else. Intelliroot's API Security Testing service delivers a structured, adversarial assessment of every layer of your API surface — authentication, authorisation, data exposure, input handling, and rate-limiting — mapped fully to the OWASP API Security Top 10.
Our CREST-certified engineers approach each engagement the way a real attacker would: starting with passive reconnaissance of API specifications and documentation, then methodically probing for broken object-level authorisation (BOLA/IDOR), mass assignment, injection flaws, JWT weaknesses, and business-logic abuse. Every finding is validated end-to-end so you receive actionable, evidence-backed results — not theoretical alerts. The final report provides risk-rated findings with exploitation proof-of-concept, remediation guidance, and a re-test credit to confirm fixes hold.
Why API Security Testing Is Non-Negotiable
APIs Are the #1 Attack Surface
Gartner predicts APIs will become the most frequent attack vector for enterprise data breaches. Every undocumented endpoint, stale version, and forgotten debug route is a door attackers actively scan for.
Authorisation Flaws Are Invisible to Scanners
BOLA and IDOR vulnerabilities require understanding your business object model. Automated tools miss them almost entirely. Manual testing by experienced engineers is the only reliable detection method.
Business Logic Bypasses Cost the Most
Attackers who understand your API can manipulate pricing, skip approval workflows, or elevate privileges — all without triggering a single security alert. These flaws require domain-aware manual testing.
Regulatory Pressure Is Mounting
RBI's IT Framework, SEBI CSCRF, and India's DPDPA mandate periodic API security assessments for financial and data-processing organisations. Non-compliance carries significant financial and reputational penalties.
Built For Your Team
What We Test
Authentication & Authorisation
- Broken Object Level Authorisation (BOLA / IDOR)
- Broken Function Level Authorisation
- JWT signature validation and algorithm confusion
- OAuth 2.0 / OIDC flow weaknesses
- API key exposure and rotation gaps
Input Validation & Injection
- SQL, NoSQL, and command injection via API parameters
- GraphQL introspection abuse and deep query attacks
- Mass assignment and over-posting
- XML external entity (XXE) in SOAP and REST
- Server-side request forgery (SSRF) via URL parameters
Data Exposure & Transport
- Excessive data exposure in responses
- Sensitive data in GET parameters and logs
- TLS configuration and certificate validation
- HTTP security headers on API responses
- Caching of authenticated API responses
Rate Limiting & Business Logic
- Resource exhaustion and denial-of-service vectors
- Lack of rate limiting on sensitive endpoints
- Business workflow bypass and step-skipping
- Negative value and boundary condition abuse
- Versioning mismatches exposing deprecated functionality
Our Approach
Reconnaissance & Specification Review
We collect all available API specifications (OpenAPI / Swagger, GraphQL SDL, WSDL), review developer documentation, and identify undocumented endpoints through traffic analysis and crawling. This phase maps the complete attack surface before any active testing begins.
Authentication & Session Analysis
We examine every authentication mechanism in depth — API key schemes, JWT validation, OAuth flows, and session token entropy. We test for common weaknesses including algorithm confusion attacks on JWTs, token fixation, and credential stuffing resistance.
Authorisation & Access Control Testing
Using multiple user roles and test accounts, our engineers attempt horizontal and vertical privilege escalation across all object types. BOLA and IDOR checks are performed against every resource identifier (integer IDs, UUIDs, slugs) in the API.
Input Handling & Injection Testing
Every parameter, header, and body field is tested for injection vulnerabilities tailored to the underlying technology stack. For GraphQL APIs we perform introspection analysis, batching attacks, and circular query depth-exhaustion tests.
Business Logic & Rate Limit Assessment
We model the intended business workflows and attempt to break them: skipping payment steps, abusing promotional logic, triggering race conditions, and exhausting resources without triggering throttling. This phase is performed manually and cannot be replicated by automated scanners.
Reporting & Re-test
Findings are documented with full reproduction steps, CVSS 3.1 scores, OWASP API Top 10 mapping, and prioritised remediation guidance. A complimentary re-test is included within 30 days to validate that critical and high findings have been resolved correctly.
Frequently Asked Questions
Deliverables
Executive Summary Report
A concise board-level summary of risk posture, key findings, and business impact — written for non-technical stakeholders and suitable for audit committees.
Technical Findings Report
Full technical detail for every finding: reproduction steps, request/response evidence, CVSS 3.1 score, OWASP API Top 10 mapping, and prioritised remediation guidance ranked by exploitability and impact.
Risk Register (CSV / XLSX)
A structured spreadsheet of all findings with risk ratings, remediation owners, and target fix dates — ready to import into Jira, ServiceNow, or your existing vulnerability management platform.
Proof-of-Concept Scripts
Where safe and appropriate, we provide working PoC scripts (Python / Burp Suite extensions) demonstrating critical findings so developers can reproduce and understand the vulnerability in their own environment.
Remediation Guidance Document
Technology-specific remediation advice for each finding class — including secure code patterns, API gateway configuration examples, and references to relevant OWASP cheat sheets.
Free Re-test Certificate
A complimentary re-test of all critical and high findings within 30 days of the report, with a signed attestation letter confirming remediation status — accepted by most regulators and auditors.
Request a Security Assessment
Tell us about your environment and security objectives. We'll design a bespoke assessment and deliver a detailed proposal within 48 hours.