# API Sec

Entry P1 category router for API security.

- Repository: https://github.com/yaklang/hack-skills (2601 stars)
- Category: Security
- License: MIT
- Last updated: 2026-09-13
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add yaklang/hack-skills --skill api-sec -g -a claude-code -y`
Codex: `npx skills add yaklang/hack-skills --skill api-sec -g -a codex -y`
Cursor: `npx skills add yaklang/hack-skills --skill api-sec -g -a cursor -y`
Gemini CLI: `npx skills add yaklang/hack-skills --skill api-sec -g -a gemini-cli -y`

## Description

Entry P1 category router for API security. Use when choosing between API recon, authorization, token abuse, and hidden-parameter workflows before any deeper API topic skill.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# API Security Router

This is the routing entry point for API security testing.

Use this skill first to decide whether the API issue is mostly recon/docs, object authorization, token trust, or GraphQL/hidden parameters, then route to a deeper topic skill.

## When to Use

- The target exposes REST APIs, mobile backends, or GraphQL endpoints
- You need to define API testing order before going into specific topics
- You want to handle object authorization, JWT, GraphQL, and hidden fields as separate tracks

## Skill Map

- [API Recon and Docs](../api-recon-and-docs/SKILL.md): OpenAPI, Swagger, version drift, hidden documentation
- [API Authorization and BOLA](../api-authorization-and-bola/SKILL.md): BOLA, BFLA, method abuse, hidden writable fields
- [API Auth and JWT Abuse](../api-auth-and-jwt-abuse/SKILL.md): bearer token, header trust, claim abuse, rate-limit bypass
- [GraphQL and Hidden Parameters](../graphql-and-hidden-parameters/SKILL.md): introspection, batching, undocumented fields, hidden parameters

## Quick Triage

| Observation | Route |
|---|---|
| Swagger or OpenAPI is present | [api-recon-and-docs](../api-recon-and-docs/SKILL.md) |
| IDs appear in URL, JSON, headers, or GraphQL args | [api-authorization-and-bola](../api-authorization-and-bola/SKILL.md) |
| JWT token visible in traffic | [api-auth-and-jwt-abuse](../api-auth-and-jwt-abuse/SKILL.md) |
| `/graphql` or batched JSON arrays are present | [graphql-and-hidden-parameters](../graphql-and-hidden-parameters/SKILL.md) |
| Registration, login, or profile updates accept extra fields | [api-authorization-and-bola](../api-authorization-and-bola/SKILL.md) then [api-auth-and-jwt-abuse](../api-auth-and-jwt-abuse/SKILL.md) |

## Recommended Flow

The rest: https://github.com/yaklang/hack-skills/blob/HEAD/skills/api-sec/SKILL.md