web-api-enumeration

name	web-api-enumeration
description	REST API discovery, GraphQL detection, parameter fuzzing.
allowed-tools	Bash Read Write
metadata	{"subdomain":"reconnaissance","when_to_use":"API enumeration, swagger, openapi, GraphQL, introspection, parameter fuzzing, REST endpoints","tags":"api-enum, graphql, swagger, parameter-discovery","mitre_attack":"T1595.003"}

Web API Enumeration & Parameter Discovery

Surface REST/GraphQL endpoints and the parameter surface of known endpoints. This sub-skill covers everything between "the directory tree is mapped" and "I know what to fuzz".

1. API Endpoint Enumeration

REST API Discovery

# Common API paths
ffuf -u https://<target>/api/FUZZ -w /usr/share/wordlists/api-endpoints.txt -mc 200,201,401,403,405

# Version enumeration
for v in v1 v2 v3; do
    ffuf -u "https://<target>/api/$v/FUZZ" -w api-wordlist.txt -mc 200,201,401,403
done

# Check for Swagger/OpenAPI docs
for doc in swagger.json openapi.json api-docs docs/api swagger/v1/swagger.json; do
    code=$(curl -s -o /dev/null -w "%{http_code}" "https://<target>/$doc")
    echo "$code $doc"
done

GraphQL Detection

# Common GraphQL endpoints
for path in graphql graphiql playground api/graphql; do
    # Introspection query
    curl -s -X POST "https://<target>/$path" \
        -H "Content-Type: application/json" \
        -d '{"query":"{__schema{types{name}}}"}' | head -c 200
    echo " → $path"
done

API Key/Token Patterns

Look for in responses:

• api_key, apiKey, access_token, bearer, jwt
• Base64-encoded blobs in cookies or headers
• Authorization header patterns

2. Parameter Discovery

# GET parameter fuzzing
ffuf -u "https://<target>/page?FUZZ=test" -w /usr/share/wordlists/params.txt -mc 200 -fs <default_size>

# POST parameter fuzzing
ffuf -u "https://<target>/login" -X POST \
    -d "FUZZ=test" -H "Content-Type: application/x-www-form-urlencoded" \
    -w /usr/share/wordlists/params.txt -mc 200 -fs <default_size>

# Header fuzzing
ffuf -u "https://<target>/" -H "FUZZ: test" \
    -w /usr/share/wordlists/headers.txt -mc 200 -fs <default_size>