Agent skill · security · davila7
API Fuzzing for Bug Bounty
This skill should be used when the user asks to "test API security", "fuzz APIs", "find IDOR vulnerabilities", "test REST API", "test GraphQL", "API penetration testing", "bug bounty API testing", or needs guidance on API security assessment techniques.
Why this skill is useful
Adds executable scripts and specific techniques for API security testing that are not commonly known.
What it needs
Requires burp-suite, python installed locally. About 5k tokens when loaded. Last updated 2026-08-06. 30,138 stars on the source repository.
What this skill does
API Fuzzing for Bug Bounty Purpose Provide comprehensive techniques for testing REST, SOAP, and GraphQL APIs during bug bounty hunting and penetration testing engagements. Covers vulnerability discovery, authentication bypass, IDOR exploitation, and API-specific attack vectors. Inputs/Prerequisites Burp Suite or similar proxy tool API wordlists (SecLists, apiwordlist) Understanding of REST/GraphQL/SOAP protocols Python for scripting Target API endpoints and documentation (if available) Outputs/Deliverables Identified API vulnerabilities IDOR exploitation proofs Authentication bypass techniques SQL injection points Unauthorized data access documentation --- API Types Overview Type Protocol Data Format Structure ------ ---------- ------------- ----------- SOAP HTTP XML Header + Body REST HTTP JSON/XML/URL Defined endpoints GraphQL HTTP Custom Query Single endpoint --- Core Workflow Step 1: API Reconnaissance Identify API type and enumerate endpoints: Step 2: Authentication Testing Step 3: IDOR Testing Insecure Direct Object Reference is the most common API vulnerability: IDOR Bypass Techniques: Step 4: Injection Testing SQL Injection in JSON: Command Injection: XXE Injection: SSRF via API: .NET Path.Combine Vulnerability: Step 5: Method Testing --- GraphQL-Specific Testing Introspection Query Fetch entire backend schema: URL-encoded version: GraphQL IDOR GraphQL SQL/NoSQL Injection Rate Limit Bypass (Batching) GraphQL DoS (Nested Queries) GraphQL XSS GraphQL Tools Tool Purpose ------ --------- GraphCrawler Schema discovery graphw00f Fingerprinting clairvoyance Schema reconstruction InQL Burp extension GraphQLmap Exploitation --- Endpoint Bypass Techniques When receiving 403/401, try these bypasses: --- Output Exploitation PDF Export Attacks DoS via Limits --- Common API Vulnerabilities Checklist Vulnerability Description --------------- ------------- API Exposure Unprotected endpoints exposed publicly Misconfigured Caching Sensitive data cached incorrectly Exposed Tok …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills davila7/api-fuzzing-bug-bounty